SHRAPNEL SHELL
MANUFACTURE
SHRAPNEL SHELL
MANUFACTURE
A COMPREHENSIVE TREATISE ON THE FORGING,
MACHINING, AND HEAT-TREATMENT OF SHELLS,
AND THE MANUFACTURE OF CARTRIDGE CASES
AND FUSES FOR SHRAPNEL USED IN FIELD
AND MOUNTAIN ARTILLERY, GIVING COMPLETE
DIRECTION FOR TOOL EQUIPMENT AND METHODS
OF SETTING UP MACHINES, TOGETHER WITH
GOVERNMENT SPECIFICATIONS FOR THIS CLASS
OF MUNITIONS
By DOUGLAS T. HAMILTON
ASSOCIATE EDITOR OF MACHINERY
AUTHOR OF "ADVANCED GRINDING PRACTICE,"
"AUTOMATIC SCREW MACHINE PRACTICE,"
"MACHINE FORGING," ETC.
FIRST EDITION
NEW YORK
THE INDUSTRIAL PRESS
1915
COPYRIGHT, 1915
BY
THE INDUSTRIAL PRESS
NEW YORK
PREFACE
The design of shrapnel and the machining of its compo-
nent parts are matters which, at the present time, are of
world-wide interest to manufacturers, engineers, toolmak-
ers, and mechanics in general. Shrapnel is used in enor-
mous quantities in the great European war, and American
machine tool builders have been called upon to provide
machines and tool equipment of the latest and most effi-
cient design to meet the demands made upon the manufac-
turers of shrapnel. Many shops are running full force,
day and night, and are months behind with their orders.
The great importance of shrapnel manufacture, at the pres-
ent time, is, therefore, unquestioned.
A small percentage of shrapnel shells are now made
from bar stock, but most shrapnel bodies are made from
forgings, formed hollow in hydraulic presses or in forging
machines. The forging processes, which are of extraordi-
nary interest, especially to those who know something of
the difficulties attending them, are, however, not finishing
processes. Whether made from the bar or forged hollow, all
shrapnel shells must be very accurately finished by ma-
chining.
This book has been brought out to meet the demands for
a treatise dealing comprehensively with the construction,
forging and machining operations, and the tool equipment
used for making the shell, fuse parts, and brass cases.
In this book are included not only the unusually complete ar-
ticles on shrapnel manufacture contained in the April, 1915,
number of MACHINERY, of which 5000 extra copies were
printed and 5000 additional reprints made, all of which
have been sold, but it also includes all other material that
has been published at various times in MACHINERY relating
to shrapnel manufacture, together with a great deal of
material obtained by the Editors especially for this book;
and, in addition to this, it contains abstracts of the official
specifications, together with line-engravings of the details
of Russian, British, and American shrapnel shell bodies,
fuses, and cartridge cases. Hence, it is believed that the
book will prove the most valuable addition to the literature
on the manufacture of munitions that has been made since
the beginning of the great war.
D. T. H.
NEW YORK, October, 1915.
CONTENTS
PAGES
CHAPTER I.
Shrapnel Shells 1-19
CHAPTER II.
Forging Shrapnel Shells 20-39
CHAPTER III.
Machining and Heat-treatment of
Shrapnel Shells 40-74
CHAPTER IV.
Machines and Tools for Shrapnel Man-
ufacture 75-142
CHAPTER V.
Making Fuse Parts 143-171
CHAPTER VI.
Making Shrapnel Cartridge Cases 172-193
CHAPTER VII.
Specifications for the Manufacture and
Inspection of the Russian 3-inch
Shrapnel Shell 194-212
CHAPTER VIII.
Specifications for the Manufacture and
Inspection of the Combination Fuse for
Russian 3-inch Shrapnel Shells 213-230
CHAPTER IX.
Specifications for the Manufacture and
Inspection of Russian 3-inch Shrapnel
and High-explosive Cartridge Cases 231-250
CHAPTER X.
Specifications for British 18-pounder
Quick-firing Shrapnel Shell 251-259
CHAPTER XI.
PAGES
Specifications for British Combination
Time and Percussion Fuses 260-275
CHAPTER XII.
Specifications for British 18-pounder
Quick-firing Cartridge Case and
Primer 276-285
CHAPTER XIII.
Specifications for American Shrapnel
Shells 286-292
INDEX 293-296
SHRAPNEL SHELL
MANUFACTURE
CHAPTER I
SHRAPNEL SHELLS
IN NAVAL, coast defense and artillery operations, sev-
eral types of explosive shells are used; the chief ones are:
the armor-piercing shell, made to pierce armor -plate be-
fore exploding; shells exploded by means of a timing fuse;
shells exploded by either a timing or percussion fuse ; and
shells exploded by percussion only. Each different shell
has some definite function to fulfill, and is designed for
that purpose. For field or artillery operations, the shrapnel
and lyddite are the two principal types used. Of these,
shrapnel is the most prominent, because of its destructive
power and its interesting mechanical construction.
Early Development of Shrapnel. The shrapnel shell
was invented in 1784 by Lieut. Henry Shrapnel, and was
adopted by the British Government in 1808. As is shown at
A in Fig. 2, the first shell was spherical in shape, and the
powder or explosive charge was mixed with the bullets. Al-
though this type of shell was an improvement over the
grape and canister previously used, its action was not alto-
gether satisfactory, as the shell, on bursting, projected the
bullets in all directions and there was also a liability of pre-
mature explosion. In order to overcome the defects men-
tioned, Col. Boxer separated the bullets from the bursting
charge by a sheet-iron diaphragm, as shown at B in Fig. 2.
This shell was called a diaphragm shell to differentiate it
from the first shell of this type.
In the shell made by Col. Boxer, the lead bullets were
hardened by the addition of antimony, and as the bursting
charge was small, the shell was weakened by cutting four
2 SHRAPNEL SHELLS
grooves extending from the fuse hole to the opposite side of
the shell. Shells of spherical shape were first fired out of
plain-bored guns, and upon the advent of the rifled gun it
was necessary to add a circular base, which was made of
wood and covered with sheet iron or steel to take the rifling
grooves. The first shrapnel shells were made of cast iron,
but a later development was to use steel and elongate the
body, reducing it in diameter. The diameter of the bullets
was also reduced so that a greater number could be con-
tained in a slightly smaller space. The improved shrapnel
was also capable of being more accurately directed.
Shrapnel Shells of Present-day Design. Shrapnel shells,
as used at the present time by the different governments,
vary slightly in construction and general contour as well
as in the constituents entering into their different mem-
bers. As shown in Fig. 1, a completed shrapnel comprises
a brass case carrying a detonating primer and the explosive
charge for propelling the projectile out of the bore of the
gun. The projectile itself comprises a forged shell that
carries the lead bullets and bursting charge. Screwed into
the front end is the combination timing and percussion fuse
which can be set so as to explode the shell at any desired
point, and from which the flame for exploding the bursting
charge is conveyed through a powder timing train and a
tube filled with powder pellets down through the diaphragm
to the powder pocket.
Of these members of a shrapnel, the shell and timing fuse
present the most interesting features from a mechanical
standpoint. The shell used by most governments is made
from a forging, machined to the desired dimensions in hand
and semi-automatic turret lathes as well as in ordinary en-
gine lathes. The fuse is an extremely accurate piece of
mechanism, and is largely produced from screw machine
parts, some of which, however, are forged previous to ma-
chining. The brass cartridge case the next member of im-
portance is drawn from a brass blank by successive opera-
tions in drawing presses, and is indented and headed. Fol-
lowing this, several machining operations are performed on
the head and primer pocket.
SHRAPNEL SHELLS
Types of Shrapnel Shells. Shrapnel shells are made in
two distinct types, one of which is known as the common
shell, and the other as the high explosive. The common shell
is a base-charged shrapnel, fitted with a combination fuse,
whereas the high-explosive shell is fitted with a combination
Fig. 1. Types of Shrapnel Shells used by the American, Russian,
German, French, and British Governments
fuse and, in addition, with a high-explosive head, the head
also bursting and flying into atoms upon impact. The high-
explosive shell is not ruptured upon the explosion of the
bursting charge in the base, but the head is forced out and
SHRAPNEL SHELLS
the bullets are shot out of the case with an increased
velocity. In the meantime, the head continues in its flight
and detonates on impact. This type of shell is not used as
extensively as the common shrapnel, and, therefore, the
common shrapnel shell alone will be taken up in the
following.
The Explosive Charge. Reference to Fig. 1 will show
that as far as the construction of the shrapnel shell and case
is concerned, there is very little difference in those emloyed
by the various governments. Starting with the cases, it
Machinery
Fig. 2.
Original Shell designed by Lieut. Henry Shrapnel and
Col. Boxer's Improvement
will be seen that these are almost identical, except for length
and the arrangement of the head for carrying the detonat-
ing primer. There is a marked similarity in this respect
between the Russian, the British, and the German, and be-
tween the American and the French. The form of the ex-
plosive charge held in the brass case differs in almost every
instance, but without exception smokeless powder in some
form or other is used. In the American shell, nitrocellulose
powder composed of multi-perforated cylindrical grains
each 0.35 inch long and 0.195 inch in diameter are used. In
the Russian case, smokeless powder of crystalline structure
is used. In the German, smokeless (nitrocellulose) powder
in long sticks and arranged in bundles is held in the case.
SHRAPNEL SHELLS 5
The French use stick smokeless powder^ 1/2 millimeter (0.0195
inch) thick by 12.69 millimeters (!/2 inch) wide. Two
lengths or rows of this powder are arranged in the case.
The British use a smokeless powder of crystalline structure
somewhat similar to the Russian, but in some cases cordite
has also been used, although of late this type of powder has
not been quite as commonly employed.
The detonating agent or primer held in the head of the
case varies in almost every type of shrapnel. Practically all
primers are provided with "safety heads," so that the shrap-
nel can be handled without danger of premature explosion.
The object, of course, of the detonating agent or primer is
to detonate or cause the sudden explosion of the explosive
charge in the shell for propelling the shrapnel out of the
field gun.
The Shrapnel Shell. The shell itself, as previously
mentioned, is made either from a forging or from bar stock.
Forgings, however, are used to a greater extent than bar
stock, because the forged shell is more homogeneous in its
structure than the bar-stock shell, and piping a serious
objection in the bar-stock shell is entirely eliminated. The
shells used by the British, Russian, and German govern-
ments are made almost exclusively from forgings, whereas
those used by the French and American governments are
made both from forgings and bar stock. When the French
shell is made from bar stock, an auxiliary base is screwed
into it to eliminate any danger of piping. Near the base of
all shells is a groove in which a bronze or copper band is
hydraulically shrunk. This is afterward machined to the
desired shape and takes the rifling grooves in the gun so as
to rotate the shell when it is expelled. The body of the shell
itself is slightly smaller than the bore in the gun, and the
rifling band, which is larger and which is compressed into
the rifling grooves, rotates the projectile, thus keeping it in
a straight line laterally during flight. The bursting charge,
which in practically all cases is common black powder, is
carried in the base of the shell and is usually enclosed in a
tin cup. Located above this is the diaphragm which is used
for carrying the lead bullets out of the shell when the burst-
6 SHRAPNEL SHELLS
ing charge explodes and distributes them in a fan shape. In
most shells, upon exploding, the nose blows out, stripping
the threads that hold the members together. It will, there-
fore, be seen that, in the explosion, the entire fuse, fuse base,
tube, diaphragm and bullets are all ejected, the shell itself
acting as a secondary cannon in the air.
The number of lead bullets carried in the 3-inch shrapnel
shells ranges from 210 to 360. In all cases, the lead bullets
are about % inch in diameter, weigh approximately 167
grains, and are kept from moving in the shell by resin or
other smoke-producing matrix. The matrix put in with the
lead bullets, in addition to keeping them from rattling, is
also used as a "tracer." It is of importance in firing shrap-
nel that the position of the explosion be plainly seen. With
large shells this is not difficult, but with shrapnel for field
guns at long range certain conditions of the atmosphere
make it difficult to see when the shell actually bursts. Vari-
ous mixtures are used to overcome this difficulty. In some
cases, fine-grained black powder is compressed in with the
bullets in order to give the desired effect. In the German
shrapnel, a mixture of red amorphous phosphorus and fine-
grained powder which produces a dense white cloud of
smoke is used, and in the Russian, a mixture of magnesium
antimony sulphide is used. The range of a 3-inch shrapnel
shell is about 6500 yards, and the muzzle velocity of the
quick-firing field gun ranges from 1700 on the American to
1930 feet per second on the Russian field gun. The dura-
tion of flight ranges from 21 to 25 seconds.
Development of Timing and Percussion Fuses. The
first fuses used in field ammunition were short iron or cop-
per tubes filled with a slow-burning composition. These
were screwed into a fuse hole provided in the shell, but
there was no means for regulating the time of burning.
Later about the end of the seventeenth century the fuse
case was made of paper or wood so that by drilling a hole
through into the composition the fuse could be made to
burn for approximately the desired length of time before
exploding the shell, or the fuse could be cut to the correct
length to accomplish the same purpose.
SHRAPNEL SHELLS 7
For a considerable time all attempts to produce a percus-
sion fuse were unsuccessful. Upon the discovery of ful-
minate of mercury in 1799, the chief requirement of a per-
cussion fuse was obtained. About fifty years elapsed, how-
ever, before a satisfactory fuse was made. The first per-
cussion fuse was known as the Pettman fuse, and comprised
a roughened ball covered with detonating composition that
was released upon the discharge of the gun. When the shell
hit the desired object, the ball struck against the inner walls
of the fuse, exploded the composition and powder charge,
thus bursting the shell. There are at the present time three
principal types of fuses in use : First, those depending on
gas pressure in the gun setting the pellet of the fuse free
this is a base fuse ; second, those relying on the shock of dis-
charge or the rotation of the shell to set the pellet free
used in nose and base fuses; third, those depending on
impact.
In shrapnel shells advantage is taken of two types of
fuses, one of which is the combination timing and percus-
sion fuse used on common shrapnel, and the other the com-
bination timing and percussion fuse of the high-explosive
type used on high-explosive shrapnel. These types of fuses
are again sub-divided, but only in the manner of construc-
tion. The most common fuse is that known as the com-
bination timing and percussion fuse of the double-banked
type. This is used in practically all shrapnel fuses except
the French. The advantage of the double ring of com-
position shown at A and B in Fig. 3 is to give a greater
length of composition and more accurate burning. Triple-
banked and quadruple-banked fuses on the same principle
have been designed, but at the present time have not been
introduced.
Operation of Combination Timing and Percussion Fuses.
The manner in which the combination timing and percus-
sion fuse is regulated to discharge the bursting charge in
the shrapnel shell is interesting and involves extremely dif-
ficult mathematical calculations. Before going into the
method of setting the fuse, it would probably be advisable
to describe briefly just how the fuse operates. As an ex-
8
SHRAPNEL SHELLS
ample of the double-banked fuse, Fig. 3 shows that adopted
by the United States government. The following descrip-
tion applies to this type of fuse.
Assume, first, that the timing ring is set at zero. The
propelling force given to the shrapnel shell in leaving the
bore of the gun is such as to sever the wire C from plunger
G. Plunger G carries a concussion primer which is dis-
charged by hitting firing pin D. The flame passes out
Machinery
Fig. 3.
American Type of Combination Timing and Percussion
Fuse used on Shrapnel Shells
through vent E, igniting the powder pellet F and the upper
end of train A, and then through the vent H. From here,
the flame is transmitted to the lower timing ring B through
vent / and the magazine J, and from there through the tube
to the bursting charge in the base of the shrapnel shell.
Assume any other setting, say 12 seconds. The vent H is
now changed in position with respect to vent F leading to
SHRAPNEL SHELLS
the upper timing train, and the vent / leading to the powder
magazine J is also changed. The flame, therefore, now
passes through vent E and burns along the upper time train
A in a counterclockwise direction until the vent H is
reached. It then passes down to the beginning of the lower
timing train and burns back in a clockwise direction to the
position of vent /, from which it is transmitted by the pellet
Machinery
Fig. 4.
Russian Type of Combination Timing and Percussion Fuse
used on Shrapnel Shells
of compressed powder in this vent to the powder magazine
J. It should be understood that the annular grooves in the
lower face of each timing train do not form complete circles,
a solid portion being left between the grooves in the ends
of each. This solid portion is used to obtain a setting at
which the fuse cannot be exploded and is known as the
"safety point." As shown in Fig. 6, it is marked S on the
adjustable timing ring.
10 SHRAPNEL SHELLS
The timing fuse shown in Fig. 3 is of the combination
timing and percussion type, and if the wire C fails to re-
lease percussion plunger G, the shell is exploded by means
of a percussion fuse which comes into use when the shell
strikes. The percussive mechanism consists of a primer K
held in an inverted position in the center of the fuse body
by a cup located beneath the percussive primer. Percus-
sion plunger L works in a recess in the base of the fuse
body and is kept at the bottom of the recess away from con-
tact with the primer by a light spring in plunger M. The
firing pin N is mounted on a f ulcrumed pin, and is normally
kept in the vertical position by means of two side spring
plungers. When the shell strikes, the impact causes the
plunger to snap up against the primer after compressing
the spring in pin M. This causes the firing of the primer
K and the explosive charge passes out through a hole in the
percussion plunger chamber, not shown, to the magazine /
and from there down to the powder in the base of the shell.
Russian Fuse. The Russian fuse shown in Fig. 4 differs
only in a few minor details from the American fuse, the
chief difference being in the arrangement of the percussive
mechanisms. The percussive plunger for the timing ar-
rangement is kept up from the firing pin by means of a
spring bushing E surrounding the body of the plunger.
This bushing is expanded by the plunger which is forced
through it due to the force of the shrapnel in leaving the
bore of the gun. The spring B in the head of the fuse
assists the plunger in expanding bushing E and in dropping
down onto the firing pin C. The flame from the exploded
primer then travels down to the powder in the shell in
practically the same way that it does in the American fuse,
except that the magazine chamber is located at D and ex-
plodes through the impact fuse chamber. The percussive
arrangement for setting the shell off by impact is slightly
different from that in the American fuse, in that the primer
and firing pin are held apart by means of springs, the
inertia of which is overcome when the shell strikes an
object.
SHRAPNEL SHELLS
11
French Fuse. With the exception of a few minor de-
tails, the timing fuses used in American, Russian, British,
German, Japanese, etc., shrapnel shells are the same. The
French timing fuse, however, as shown by the diagram
Fig. 5, operates on an entirely different principle. In this
fuse, the firing for the timing train is contained in a sealed
tube of pure tin and is wound spirally around the head of
the fuse. Inside of the head is the ignition arrangement.
To set the timing part of this fuse, it is placed in a fuse-
setting machine attached to the field gun and, by forcing
down a handle on this device, a piercing point is thrust
through the outer cap of the fuse, penetrating to the in-
t e r i o r space of the
head as shown at A.
Upon the discharge of
the shell from the gun,
the gas pressure forces
firing pin B back, hit-
t i n g the percussive
primer C. This causes
a flame which passes
out through the open-
ing previously punch-
ed at A and ignites the
"rope" powder fuse
which is wound around
the head of the fuse
body. This t y p e o f
fuse is also provided with a fuse which sets off the shell
by impact should the timing fuse fail to work. The head
of the fuse is covered with a cap with holes for the pierc-
ing point, and the whole cap can be shifted around for
a short distance and set by the corrector scale marked
on the body, as shown in Fig. 1. A projection on the cap
engages a recess in the fuse-setting machine and provides
for this movement.
Firing of Shrapnel. The accuracy with which a shrap-
nel can be exploded in the air at any desired point is re-
markable, considering the number of variable quantities
Machinery
Fig. 5. French Type of Combination
Timing and Percussion Fuse
12
SHRAPNEL SHELLS
that enter into the construction of the timing fuse and
powder train, etc. The calculations necessary for finding
the correct setting on the timing ring involve, however, the
use of higher mathematics and are consequently not within
the scope of this treatise.
In Fig. 6, the timing ring used on the American fuse is
shown. Here it will be seen that the ring is provided with
twenty-one graduations corresponding to twenty-one
seconds in the duration of flight of the projectile. It will
also be noticed that
the spacing of the
graduations differs.
The reason for this
is found in the rela-
tion of the vents,
the positions of the
lower timing train,
the trajectory of the
flying missile, and
the decrease of ve-
locity.
Diagram Fig. 7
shows in an inter-
esting manner just
how a shrapnel is
fired. The range is
approximately o b -
tained by panoram-
ic sights or other
means, and a test
shell fired, the point of explosion noted, and the necessary
corrections made. A table which has been worked out for
different distances is then used. In Fig. 7 the diagram
shown pertains to the American quick-firing field gun hav-
ing a muzzle velocity of 1700 feet per second and the Ameri-
can shrapnel of 3-inch size. It will be noted that at 2000
yards the terminal velocity of the shrapnel is 1038 feet per
second and the time of flight for the projectile 4.75 seconds.
In other words, the timing train to explode the shrapnel at
Machinery
Fig. 6. Diagram showing how Timing Ring
on the American Combination Timing
and Percussion Fuse is laid out
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14 SHRAPNEL SHELLS
in the base of the projectile, and the cartridge case that car-
ries the powder charge used in propelling the projectile out
of the bore of the gun. A high-explosive shell also com-
prises three principal parts, but the projectile, instead of
carrying a charge of bullets and black powder, is filled with
a high-explosive material, which, when detonated, bursts the
body of the projectile into small pieces that are thrown off
with great velocity and destructive effect. Shrapnel is
used against troops in the open field, whereas high-explosive
shells, which may be either of the ordinary or of the armor-
piercing type, are used against fortifications, etc.
Classification of Explosives. The explosives used in
shrapnel and high-explosive shells may be divided into three
general classes: 1. Progressive or propelling explosives
known as "low" explosives. 2. Detonating or disrup-
tive explosives known as "high" explosives. 3. Detona-
tors known as "fulminates." The first of these includes
black gun powder, smokeless powder, and black blasting
powder. The second, dynamite, nitroglycerine, gun cotton,
etc. The third includes chiefly fulminates and chlorates.
In all classes of explosives, the effect of the explosion is
dependent upon the quantity of gas and the heat developed
per unit of weight and volume of the explosive, the rapidity
of the reaction, and the character of the confinement, if any,
of the explosive charge.
Low Explosives. For certain explosives, such as smoke-
less powder, the explosive action does not differ in princi-
ple from the burning of a piece of wood or other combustible
material. The combustion is very rapid, but is a surface
action, progressing from layer to layer until the en-
tire grain is consumed. Such materials are known as "low"
explosives, although the power developed through the com-
bustion of a unit weight may be very great. The progres-
sive emission of gas from a low explosive, such as burning
gun powder, produces a pushing effect upon a projectile
without unduly /straining the gun, whereas the sudden
conversion of an equal weight of a high explosive, such as
nitroglycerine, into gas, would develop such high pressures
as to rupture the gun.
SHRAPNEL SHELLS 15
High Explosives. In high explosives, such as nitrogly-
cerine, gun cotton, picric acid, etc., the progress of the ex-
plosive reaction is not by burning from layer to layer, but,
instead, consists of an initial breaking up of the molecules,
giving rise to an explosive wave, which is transmitted with
great velocity in all directions throughout the mass, and
causes it to be converted almost instantly into a gas. The
velocity of this explosive wave has been determined, for
some materials, to be more than 20,000 feet, or approxi-
mately four miles, per second.
Detonators or Fulminates. The action of fulminates is
much more powerful than either the low or high explosives
described. They can be readily detonated by slight shock
or by the application of heat, and are used in primers, for
setting off the propelling charge in a cartridge case, and in
fuses, either of the plain percussion or of the combination
time and percussion types. The most common fulminate
is made by dissolving mercury in strong nitric acid and then
pouring the solution into alcohol. After an apparently vio-
lent reaction, a mass of fine, gray crystals of fulminate of
mercury is produced. The crystalline powder thus pro-
duced is washed with water to free it from acid and is then
mixed with glass ground to a fine powder. Because of its
extreme sensitiveness to heat produced by the slightest
friction, it is usually kept soaked in water or alcohol until
needed.
Manufacture of Black Powder. Black powder, because
of its "pushing" effect when exploded, is used extensively
as a base charge for shrapnel shells in expelling the bullets
from the projectile. It comprises three principal elements
in about the following proportions : 75 parts of saltpeter,
15 parts of charcoal, and 10 parts of sulphur. These in-
gredients must be absolutely free from impurities and, in
manufacturing, great care is taken in refining the saltpeter
and sulphur, and in burning the charcoal, to prevent the
introduction of any foreign substances. After purification,
the ingredients are carefully weighed in the proper propor-
tions and mixed for about 5 minutes in a revolving drum
provided with mixing arms. The mixed charge is now ground
16 SHRAPNEL SHELLS
for several hours, the charge being moistened occasionally
with distilled water, the resulting mixture being what is
called a "milk cake." It is then reduced to fine meal in a
machine having Tobin bronze or gun-metal rollers, after
which it is compressed under hydraulic pressure.
The next operation comprises the granulating of the pow-
der, which is done in a strong Tobin bronze or gun-metal
framework carrying two pairs of toothed and two pairs of
plain Tobin bronze or gun-metal rollers. The "cake" is cut
into pieces by these rollers and falls on screens which sift
it into grains of the required size. The grains are then
separated from the dust in a revolving screen, and the high
polish or glaze is produced by putting the powder into
drums or glazing barrels, which revolve constantly for
several hours. Graphite is generally used to provide the
glazing effect. The powder is now dried in a stove heated
by steam pipes, and is spread upon canvas trays placed
on shelves.
Manufacture of Smokeless Powder. Smokeless pow-
der, which is used in various forms in cartridge cases, was
discovered in 1846 by a German chemist Schoenbein. The
chief ingredient of smokeless powder is cotton. The por-
tion of cotton used is generally the short fiber. The
first attempts to produce gun cotton were unsatisfactory,
and several very serious explosions occurred. Many of the
difficulties in its manufacture were overcome by an Aus-
trian, von Lenk. Still further progress was made by a
Swedish engineer, Alfred Nobel, and the improved explo-
sive was patented in 1888 under the name of "ballistite."
One of the principal smokeless powders is known as "cor-
dite", this name being derived from the cord-like form it
assumes in manufacture. The first compositions of cordite
were: 58 per cent of nitroglycerine; 37 per cent of gun
cotton; and 5 per cent of mineral jelly. This composition,
after considerable use, was found to have a slight deterio-
rating effect on the bore of the gun, and after ten years'
use was modified to the following proportions : 30 per cent
of nitroglycerine ; 65 per cent of gun cotton ; and 5 per cent
of mineral jelly.
SHRAPNEL SHELLS 17
The brand of smokeless powder used most extensively as
a propelling charge in shrapnel or high-explosive shells is
known as nitrocellulose, and, as is common with cordite, the
base of this is cotton, as previously explained. It is manu-
factured as follows: After bleaching and purifying, the
cotton is run through a picker which opens up the fibers
and breaks up any lumps. It is then thoroughly dried and
is ready for nitration. The most generally used method of
nitration is to put the cotton into a large vessel filled with
a mixture of nitric and sulphuric acids. The sulphuric
acid absorbs the water developed in the process of nitration,
which would otherwise too greatly dilute the nitric acid.
After a few minutes' immersion, the pot is rapidly rotated
by power, and the acid permitted to escape. Following
this, the nitrated cotton is washed for a short time and then
removed from the nitrator or pot and repeatedly washed or
boiled to remove all traces of free acid. As the keeping
qualities of the nitrated cotton are dependent upon the thor-
oughness with which it is purified, the specifications for
powder for the United States army and navy require that
the nitrocellulose shall be given at least five boilings at this
stage of the manufacture, with a change of water after
each boiling, the total time of boiling being forty hours.
Following this preliminary purification, the nitrocellulose
is cut up into shorter lengths, by being rapidly run between
cylinders carrying revolving knives. This operation
known as "pulping" is necessary because of the difficulty
experienced in removing the free acid, unless the fibers
are cut up into short lengths.
After pulping, the nitrocellulose is given six more boil-
ings, with a change of water after each, followed by ten
cold water washings. The material is now known as gun
cotton or pyrocellulose. Previous to adding the solvent,
this must be free from water. This is generally accom-
plished in a circular wringer, and in addition by compress-
ing the pyrocellulose into solid blocks. Alcohol is forced
through the compressed mass. Ether is then added to the
pyrocellulose already impregnated with alcohol, the relative
proportions being two parts, by volume, of ether to one
18 SHRAPNEL SHELLS
part of alcohol. After the ether has been thoroughly in-
corporated in a kneading machine, the material is placed
in a hydraulic press and formed into cylindrical blocks
about 10 inches in diameter and 15 inches long. It is then
transferred to a finishing press where it is again forced
through dies and comes out in the form of long strips or
rods, which are cut into pieces of the length and widths
required. It is in this finishing process that the various
governments differ in their methods of manufacture. The
United States Government uses a short perforated circular
block, whereas the French use flat sticks about 0.0195 inch
thick by % inch wide. Two lengths or rows of these sticks
are arranged in the cartridge case. The cut up pieces are
subjected to a drying process which removes nearly all the
solvent and leaves the material in a suitable condition for
use. The drying process is a lengthy one, amounting to as
much as four or five months for powder in large pieces.
Upon completion, the powder is blended and packed in air-
tight boxes.
Manufacture of High Explosives. The explosive charges
used in high-explosive shells are known by various trade
names, such as: emmensite, lyddite, melinite, maximite,
nitrobenzole, nitronaphthaline, shimose, trinitrotoluol, tur-
penite, etc. The base of such explosives as emmensite, max-
imite, lyddite, melinite, and shimose, is picric acid, which
is secured from coal tar, subjected to fractional distillation.
The liquid which comes off when this is raised to a tem-
perature of 150 degrees C. is called "light" oil, and when
these light oils have been again distilled, the next fraction
or "middle" oil yields phenol or carbolic acid. This sub-
stance when nitrated gives off picric acid. Experiments
with lyddite shells showed their behavior to be very erratic,
some exploding with great effect, while others gave disap-
pointing results. This was due to the fact that picric acid
requires a powerful detonator to obtain the highest explosive
effect. The use of such a detonator, however, is dangerous,
and extensive experiments have brought forth a new high
explosive known as trinitrotoluol generally termed T. N.
T. Although the explosive force of trinitrotoluol is slightly
SHRAPNEL SHELLS 19
less than that of picric acid, the pressure of the latter being
135,820 pounds per square inch as against 119,000 pounds
for trinitrotoluol, its advantages more than compensate for
the difference.
Trinitrotoluol is obtained by the nitration of toluene,
contained in the crude benzol distilled from coal tar and
washed out from coal gas. The crude benzol contains
roughly :
Per cent
Benzine 50
Toluene 36
Xylene 11
Other substances 3
Toluene to be used for the manufacture of trinitrotoluol
should be a clear water-like liquid, free from suspended
solid matter, and having a specific gravity of not less than
0.868, nor more than 0.870, at 15.5 degrees C. Trinitrotol-
uol when pure has no odor and is a yellowish crystalline
powder which darkens slightly with age. It cannot be
exploded by flame or strong percussion, and a rifle bullet
may be fired through it without any effect. When heated
to 180 degrees C., it ignites and burns with a heavy black
smoke; but when detonated by a fulminate of mercury
detonator, it explodes with great violence, giving off a black
smoke.. Shells containing this explosive, first used on the
western battle front, were given such names as "coal boxes,"
"Jack Johnsons," "Black Marias," etc., by the allies.
The Russians and Austrians use a high explosive known
as ammonal in which 12 to 15 per cent of trinitrotoluol is
mixed with an oxidizing compound, ammonium nitrate, a
small amount of aluminum powder, and a trace of charcoal.
This high explosive gives somewhat better results than
plain trinitrotoluol, but has the one disadvantage of easily
collecting moisture, and consequently must be made up in
air-tight cartridges. The British are now using an im-
proved compound of this character, which is so prepared
that trouble is not experienced with the collection of
moisture.
CHAPTER II
FORGING SHRAPNEL SHELLS
WITHIN the last few months, many methods have been
suggested for making shrapnel forgings, but a compara-
tively small number have been put into use. Practically
speaking, no two governments have adopted the same
method. The Russian government uses double-acting hori-
zontal hydraulic forging presses in which two operations
are performed at the same time on different forgings. For
instance, while the punch in one end of the machine is
piercing a heated billet, the ram on the return stroke per-
forms the hot drawing operation on another shell located
at the opposite end of the machine. In this way a shell is
completed at each cycle of the machine forward and re-
turn stroke. The French government, up to a short time
ago, used steam hammers for this purpose, and produced
shrapnel forgings in practically the same manner as a drop-
forging is made, the punch being carried in the ram of the
press and the die held on the bed. This is rather a slow
process and requires more than one heating to complete
the forging. The German government uses a horizontal
hydraulic forging press for piercing the billet and a steam
driven machine for drawing the forging, which receives its
motion from a rack and pinion. This method has the ad-
vantage over the hydraulic press of being more economical
in the consumption of power.
The methods followed by different concerns in this coun-
try and Canada, at the present time, differ to a large ex-
tent. Some manufacturers are using a method that dates
back as far as 1890, as will be described later. Others are
using a more improved method developed about 1895,
whereas about three concerns are using a still more im-
proved method developed within the past year.
Caley Method of Making Shrapnel Forgings. The first
method (known as the Caley process) of making shrapnel
forgings in this country had its inception about 1890 and
20
FORGING SHRAPNEL SHELLS
21
was used almost exclusively until 1895. This comprised
a slug-forming and billet-piercing operation followed by a
successive reduction and elongation of the forging through
drawing dies The order of these operations is shown dia-
grammatically in Fig. 1. The information given herewith
pertains to the making of a forging for a 3-inch shrapnel
shell. As shown at D, a billet of steel 3*4 inches in diame-
ter and 6% inches long was cut off from a bar with a cold
Machinery
Fig. 1.
Diagram showing Caley Process of making Shrapnel
Forgings in Hydraulic Forging Presses
saw, and formed into a cone shape under a vertical hy-
draulic press having a capacity of 100 tons. The billet was
heated in a furnace to about 1900 degrees F., dropped into
the impression in the die and forced into shape by a hy-
draulic plunger having a depression in the lower end which
centered the blank. The result of this operation is shown
at F.
Machinery
22
Fig. 2. Watson-Stlllman Hydraulic Forging Press of the Vertical
Type used for making Shrapnel Forgings
FORGING SHRAPNEL SHELLS 23
The next step was to anneal the billet, after which it
was pierced as shown at C, and at the same time slightly
elongated. This operation was handled in a hydraulic
press of the type shown in Fig. 2. On a 0.70 per cent
carbon steel billet the pressure on the punch in the pierc-
ing operation was 20,000 pounds per square inch, and the
machine used was a vertical hydraulic forging press of the
type referred to having a capacity of 100 tons. From the
piercing operation the forging was taken direct without
annealing to the horizontal hydraulic draw press, and, as
is shown at H, was located on a punch and forced through
a series of drawing dies which gradually reduced the shell
to the correct diameter, 3Vs inches, and drew it out to
the required length, about 8% inches.
A point worthy of attention is the preparation of the
cone-shaped billet. The smallest end was made slightly
smaller than the smallest reduction die in the series. The
reason for this was that if any drawing were done on the
end of the shell the front corner would be drawn over and
deformed, increasing the amount of machining required.
The drawing dies in this case were six in number, as shown
at H, and were reduced on a sliding scale of the following
proportional reductions. First, 0.100 inch; second, 0.080
inch; third, 0.060 inch; fourth, 0.040 inch; fifth, 0.030
inch ; and sixth, 0.020 inch. This gave dies of the following
sizes, in inches, starting with the largest in the series : 3.355,
3.275, 3.215, 3.175, 3.145, and 3.125.
The shape given to the drawing edges of the dies is of
prime importance. The mouth or entering side of the hole
was beveled to an angle of 20 degrees leading to a liberal
curve which terminated in a land 1/16 inch wide. The
shape was finished off with a %-inch radius. These dies
were made from chilled cast iron and were held in position
as shown at H y being slipped into a pocket in the frame of
the machine, as shown at /. The punches for the coning,
piercing and hot drawing operations were made from spe-
cial hot punching steel. The first drawing die in the series
lasted the longest because the metal was hotter at this point
than when it was drawn completely through the dies. As
24
FORGING SHRAPNEL SHELLS 25
a rule, the last drawing die turned out 100 shells before
being worn or scored. Then it was reground to a larger
size and used again. The drawing punch was lubricated
occasionally with graphite. After drawing, the forging is
annealed to obtain the proper physical qualities. This
method of making forgings for a 3-inch shrapnel shell is
capable of producing 400 in ten hours.
Holinger Method of Making Shrapnel Forgings. About
1895 the following method, known as the Holinger process
of making shrapnel forgings, was devised. Instead of
making the billet conical in shape before piercing, this pre-
liminary operation was dispensed with, and to facilitate the
work, as well as to reduce the friction of the flowing metal,
the arrangement of the piercing punch and die was changed.
This process is shown in Figs. 3 and 4, and was accom-
plished in a hydraulic press provided with two cylinders,
one located at the bottom and the other at the top of the
press.
The operation was as follows: The die a was held in a
movable frame b and the piston c acted first. The first
position after the billet was dropped into the die is shown
at B. Here the die a and punch d remained stationary
while the piston c descended, pushing the billet through
the die and over the punch. When the piston reached the
end of its stroke, as shown at C, the lower cylinder began to
act and the frame carrying the die was raised. This frame,
as shown at D, carried a stripper plate e which removed the
pierced billet from the punch and located it so that it could
be picked off with a pair of tongs. A subsequent operation
of hot-drawing as shown at E, Fig. 4, was required, which
is similar to that described in the first method. The method
just described was used chiefly for 6- and 8-inch shrapnel
and projectile forgings, and at the present time is still used
for 3- and 6-inch shell forgings. It requires much less
power and turns out a better and more concentric forging
than the method previously described. The production on
8-inch shells is about 180 in ten hours, and 250 on the
3-inch shell.
FORGING SHRAPNEL SHELLS 27
Later Methods of Forging Shrapnel Shells. The in-
creased demand for shrapnel within the last few months
has been instrumental in bringing about a radical improve-
ment in the production of forged shells. Previously, the
aim was to get the internal diameter as close as possible to
the finished size and to do comparatively little machining
on it; in fact, this is still, in a great number of cases, one
of the requirements. While at first glance this would ap-
pear to be the logical way of handling the work, on further
investigation it is found that the forging of the shell to
the correct size is much more expensive than to leave suffi-
cient metal to machine all over. In the first place, a hy-
draulic machine of 100 tons capacity costs considerably
more in initial outlay than a turret lathe, and in the second
place it is more expensive to operate. The cheapest method
of making a shrapnel forging is to rough-forge it to ap-
proximately the correct shape and then finish to exact shape
and diameter in turret lathes or semi-automatic chucking
machines. This simplifies the forging process and also de-
creases the production costs.
One of the later methods of making shrapnel forgings
is shown diagrammatically in Fig. 5. A billet of steel
6% inches long by 3 5/16 inches in diameter is heated to a
temperature of from 1900 to 2100 degrees F., and then
dropped into the impression in the die a held in a special
cast-steel die-holder b. To do this, die a is drawn out from
beneath the punch, punch guide c removed, and the billet
dropped in. Then the guide is replaced and the die-holder
slid in until it contacts with the stop d. The press is now
operated, and, as shown at B, advances, piercing the billet
and making the metal flow up around the walls of the
punch.
The punch now retreats, carrying the centralizing guide c
with it. The die-holder is now drawn out from under the
punch onto a bracket projecting from the bed of the press.
The high-carbon steel, hardened block e then drops out of
the die, as is also the case with the finished forging. This
block e, of course, is heated up to a considerable extent due
to the hot metal resting on it so that several blocks of this
28 FORGING SHRAPNEL SHELLS
kind are provided. In the illustration, as shown at C, cen-
tralizing guide c is shown attached to the punch. In actual
operation this is not the case. When the punch rises, guide
c is stripped from it by stripper plate / so that the guide
is gripped with tongs and laid down on the bed of
the press until a fresh heated billet has been placed in the
die impression ready for the next piercing. The punch is
made from special hot punching steel and the die from
Fig. 6. Producing Shrapnel Forgings in a 750-ton Hydraulic
Forging Press
chilled cast iron. The production of forgings by this
method for a 3-inch shrapnel shell is about 600 in ten
hours.
The amount of metal left for machining by this method
varies from Vs to 3/16 inch on the internal and external
diameters. The forging after annealing is then machined
FORGING SHRAPNEL SHELLS
29
inside and out on turret lathes, or semi-automatic chucking
machines. The accepted method is to first machine the in-
ternal diameter and then hold the shell on an expanding
arbor and machine it on the external diameter.
Producing Shrapnel Forgings in Hydraulic Presses. In
the foregoing description various principles of making
shrapnel f orgings were described. Owing to the large num-
ber of f orgings lately required, practically all types of forg-
ing presses and power forging machines have been used.
Fig. 6 shows how one manufacturer is solving the problem.
Fig. 7.
Piercing Billets for Shrapnel Forgings in a
750-ton Hydraulic Forging Press
Wood'
The machine used is an R. D. Wood Co., 750-ton hydraulic
forging press; this performs both the billet piercing and
drawing operations. The forgings turned out on this ma-
chine are for the British 18-pound shell, and the billet is
3% inches in diameter by 4i/ 2 inches long. The first oper-
ation, piercing the billet, is done by the punches and dies
shown in Fig. 7. The billet is heated in a furnace to a
temperature of 2000 degrees F., and then quickly removed
FORGING SHRAPNEL SHELLS
and placed in the dies. The press is now operated, pierc-
ing two billets at the same time. The pierced billet is S 1 /^
inches in diameter by ?V& inches long.
A complete batch of pierced billets is first put through,
then the pierced billets are taken to the furnace again and
heated to 2000 degrees F. The punches and dies in the cen-
ter of the illustration Fig. 8 are used for finish-drawing the
forging by drawing it out to 31/2 inches in diameter by 11
inches long. This method is only temporary and will be
Fig. 8. Drawing Shrapnel Forgings in a "Wood'
Hydraulic Forging Press
750-ton
replaced shortly by three R. D. Wood four-post hydraulic
presses. The piercing operation will be handled on one
press of 350 tons capacity, and the drawing operations on
two presses of 200 tons capacity.
Making Shrapnel Forgings in Power Forging Machines.
One of the latest developments in the art of producing
forgings for shrapnel shells is the adaptation of the power
forging machine to this work. As has been previously men-
tioned, there are several methods of producing shrapnel
FORGING SHRAPNEL SHELLS
31
shells, and as it has been conclusively proved that the forged
shell is superior to the shell made from bar stock, it is only
natural that several methods for making the f orgings would
be developed. In the forging machine method, a bar slightly
larger than the finished diameter of the forging is cut off,
making a billet about 5V& inches long. This billet, for a 3-
inch shell, weighs about 9% to 91/2 pounds.
The billet is heated to a white heat in a furnace, the tem-
perature being about 2000 degrees F., depending on the car-
bon content and other constituents in the steel, and is then
placed in the lower impression of the forging die. The
Fig. 9. Examples of Shrapnel Forgings turned out on a Power
Forging Machine
machine used for this size of forging is a standard upset-
ting and forging machine provided with a special crank-
shaft. Upon being operated, the lower plunger, which is
larger than the diameter of the powder pocket in the shell,
advances and pierces the billet. The pierced billet is then
raised to the next impression, and the machine again oper-
ated. The second punch is longer than the first and smaller
in diameter. The billet is forced up on this punch, which
reduces it in diameter and increases its length. After the
second impression the partially formed shell is then placed
in the third or final die impression, where it is given two
blows, being given one-half turn after the first blow to
form it more perfectly. The operations just enumerated
32 FORGING SHRAPNEL SHELLS
are performed in one heating of the billet, and the produc-
tion of a 3-inch shell ranges from 400 to 450 in ten hours.
The dies for this work are, of course, constructed upon a
somewhat different principle from the ordinary forging
die, because in this case it is necessary to make the metal
flow up on the punches. The dies, therefore, are so con-
structed that they recede as the punch advances, which
tends to make the metal flow up on the punch. The prac-
ticability of this method is well illustrated by the samples
shown in Fig. 9. Here D is the rough forging just as it
comes from the machine, with the exception that the mouth
has been trimmed. C is a section of a shell made from
low-carbon steel about 0.30 per cent carbon; B is a shell
made from 0.50 per cent carbon, 3% per cent nickel steel.
This has been rough-turned, as the illustration shows. The
homogeneity of the forgings is clearly indicated. A is a
forging made from low-carbon steel, finish-turned.
One of the most interesting points about this method is
its cost as compared with shells made from bar stock. To
produce a 3-inch shell from bar stock requires about 22
pounds of material, and on metal costing 10 cents per
pound, a bar shell exclusive of machining costs $2.20;
to produce the same shell on a power forging machine re-
quires about 9% to 9% pounds, and figuring on 10 cents
per pound the cost for the material is only $1 a saving of
$1.20 on each shell. Furthermore, the production of shells
from bar stock on automatic machines is about twelve to
fifteen per day. The number of forgings that can be
turned out in the same time is 400 to 450, and the number
that can be machined in this time varies from forty to
fifty for two operations. It is therefore evident that the
production of shells by forging is far superior to the bar
method, and the forged shell is more satisfactory from
every standpoint.
Forging Shrapnel in a Power Press. Another interest-
ing development in the forging line is shown diagrammati-
cally in Fig. 10. This method comprises three operations,
and is handled in a No. 80!/2 Bliss press capable of exert-
ing a pressure of 1200 tons. A billet 3*4 inches in diame-
FORGING SHRAPNEL SHELLS
33
ter by 3% inches long is heated in a furnace to 1976 degrees
F. and then quickly placed in the die shown at A. The
press is operated, and the punch in descending pierces the
billet, being guided by the guide a, as shown at B, which
Machinery
Fig. 10. Diagram illustrating Method of piercing and drawing
Shrapnel Forgings in a Bliss Power Press
34 FORGING SHRAPNEL SHELLS
also acts as a stripper. The forging retains its heat to a
certain extent after this operation, the temperature being
about from 1380 to 1425 degrees F. This is sufficient to
perform the second minor operation which, as shown at C
and D, consists in forcing the heated billet into the die-
block to reduce the diameter of the lower end and facilitate
the succeeding operation. This reducing operation is per-
formed with the same type of punch as is used in the suc-
ceeding operation, and the die-block is simply laid on top
of a bolster while the reducing is being done.
The final forming or drawing of the forging is accom-
plished as shown at E and F, the same type of press, viz.,
a Bliss No. 80 V power press, being used for this purpose.
The pierced billet is now heated to 1976 degress F., and
is then forced through the three drawing dies b, c and d,
by the punch e. The first die is 3 5/16 inches in diameter
and reduces the forging from 3% inches to this size. The
second is 3 7/32, and the third, or last, 3Vs inches in diame-
ter. The forging, after being forced through the dies, is
stripped from the punch by plates /, and as it still retains
a temperature of 1475 degrees F. sufficient for annealing
is thrown down on the sand to cool off. The billet pierc-
ing and drawing dies, shown in the illustration, were made
from 50-point carbon steel, hardened. This gave fair re-
sults, although chilled cast-iron dies would prove even more
satisfactory. The punches were made from several differ-
ent materials such as chrome-vanadium, 70-point carbon
steel, and unannealed malleable casting. Of the three ma-
terials, the latter gave the most satisfactory results, in that
pitting was reduced to a minimum. Of course, it was nec-
essary to grind the malleable casting to shape.
Flow of Hot Metal When Pierced. In the manufacture
of shrapnel shell forgings, the first operation is that of
piercing, and to accomplish this satisfactorily, it is neces-
sary to understand the action of a piercing punch on a
semi-plastic billet of steel. There are certain fundamental
laws governing the flow of metals under pressure and a
study of these is of exceptional interest. An attempt has
been made in Fig. 11 to illustrate diagrammatically some of
FORGING SHRAPNEL SHELLS
35
the principles involved, and in the following discussion it
should be understood that the billet is made from 50-point
carbon, 60-point manganese steel, 6i/ 2 by 3 5/16 inches in
diameter.
At A a round-end tapered punch is shown in contact
with the heated billet, and the lines show the possible flow
of the metal, i. e., the material commences to "pack" at
the end of the punch. In this case the walls of the die are
Fig. 11. Diagram illustrating Flow of Hot Metal while being pierced
straight. At B the billet is being pierced, and the result-
ant effect on the flow of the metal is indicated. Here it
will be seen that the pressure increases as the punch de-
scends, because of the wedging action on the metal and
the friction between the surfaces of the sides of the punch
and die. The pressure on the end of a punch of this shape
is about 20,000 pounds per square inch.
By leaving the sides of the die of the same shape as at B,
but making the end of the punch square instead of round
36 FORGING SHRAPNEL SHELLS
and not tapered, different action is caused. When the flat
punch, as shown at (7, first contacts with the metal, the
pressure required is greater than at A, but as soon as the
metal commences to flow as at Z), the pressure decreases.
For instance, suppose the pressure required at B to pierce
the billet was 100 tons ; on the same material at D, the re-
quired pressure would be only 70 tons a decrease of 30
per cent. The metal, however, does not follow the sides
of the punch as closely at D as at B, and this accounts in
part for the reduction of power required. The action of
hot flowing metal on the face of a square punch is just the
reverse of what would naturally be expected. Instead of
Fig. 12. Shrapnel Shell Head and Diaphragm produced in
a Power Forging Machine
the punch wearing away at the edge, the center first shows
signs of wear as indicated at e. Seams are opened up in
a radial direction caused by the hot metal attacking the
softest parts in the face of the punch.
Again, a different condition exists to that shown at B
and D, when both the die and the punch are tapered as
shown at E. Here the friction of the extruded metal on the
walls of the die and sides of the punch is excessive, and it
is practically impossible to produce a satisfactorily pierced
billet in this manner. From a theoretical standpoint, the
conditions shown at F are ideal. Here the sides of the
FORGING SHRAPNEL SHELLS
37
punch are straight, the end flat, and the walls of the die
taper or increase in diameter toward the bottom. In this
case the friction of the flowing metal is greatly reduced
because of the lessening of the wedging action. Other con-
siderations, however, make this method impracticable.
A still greater reduction in the pressure necessary to
pierce a billet is shown at G. Here a square billet instead
Fig. 13. Diagram illustrating Method of producing Shrapnel Shell
Heads in a Power Forging Machine without any
Waste of Stock
of a round one is being pierced. In the plan view it will
be noticed that the friction on the walls of the die is greatly
reduced, and the pressure continues low until the extruded
billet contacts all around with the surface of the die. The
completed product, however, is inferior to that made from
a round billet. From the previous remarks, it will be seen
that a punch and die that would best meet the requirements
38
FORGING SHRAPNEL SHELLS
is one having a rounded end as at B, straight sides as at D,
and straight walls in the die. The most satisfactory punch
and die for piercing shrapnel f orgings when all the variable
conditions are considered would be as shown at H.
Forging the Shrapnel Head. The shrapnel head shown
at A in Fig. 12, that screws into the end of the shell and in-
A LJ
STOP
6
-BAR STOCK
Machinery
Fig. 14. Diagram illustrating Method of making Shrapnel Shell
Diaphragms in a Special Type of Power Forging Machine
to which the fuse body is screwed, is made from a forging
of low-carbon steel for the French shell. One method of
producing this, which is of unusual interest, is shown in
Fig. 13. A power-driven forging machine equipped with a
special set of tools is used for this purpose. A bar of steel
of the same diameter as the hole in the finished forging,
FORGING SHRAPNEL SHELLS 39
in this case li/a inch, is gripped in the dies as shown at A,
and is upset by means of a plunger a, forming an upset on
the end of the bar shown to the right. The upset bar is
now placed in the second impression of the gripping dies,
as shown at B. By way of explanation, it should be stated
that the views of the dies shown at A, B, and C are sec-
tions taken in a horizontal plane at each stage or die im-
pression. Upon gripping the upset forging in the second
impression in the dies, the plunger b advances and forms
an annular groove in the face of the forging, at the same
time increasing its width as shown at c.
The forging, still integral with the bar, is now quickly
removed and placed in the last impression of the dies.
The diameter of the hole in these dies is larger than the bar,
allowing it to slip back as the punch advances to punch
the hole in the forging. When the punch moves forward
it carries with it the spring-operated sleeve d, thus finish-
ing the forging in one heat. This method of forging is
very satisfactory, producing a homogeneous forging at the
rate of 1500 in ten hours.
Forging the Steel Diaphragm. The steel diaphragm
shown at B in Fig. 12 is made from low-carbon steel in a
special type of forging machine operated similarly to a
hot-pressed nut machine. That is to say, the bar, instead
of being fed in from the front, as in a regular forging ma-
chine, is fed in from the side. The manner in which this
is accomplished is shown in Fig. 14. A flat bar of steel
2% inches wide by % inch thick, heated to the proper tem-
perature for a distance of three feet, is fed across the face
of the die as at A and located by stop b. Punch c then
advances and cuts out a blank of the required diameter,
forcing it into the die, as shown at B. The metal is now
confined between the faces of punches d and c and in die a,
and is forged to the required shape. The next step is shown
at C, where punch d advances and forces the formed forg-
ing out of the die. The production on this diaphragm is
in the neighborhood of from 8000 to 10,000 in ten hours.
CHAPTER III
MACHINING AND HEAT-TREATMENT OF SHRAPNEL
SHELLS
SHRAPNEL shells are manufactured either from bar
stock or forgings. The bar-stock method, however, is not
considered as satisfactory as forging because of piping, so
that the greater number of shrapnel shells made at the
present time are turned out from forgings. The first step,
therefore, in the making of a shrapnel shell is to cut off a
billet of the required length from a bar of steel of the nec-
Fig. 1. Shrapnel Shells in Various Stages of Manufacture
essary constituents. In the making of an 18-pound shrap-
nel shell, the billet is cut off from a bar of 46-point carbon,
60-point manganese steel in machines of different types.
One way of doing this, as shown in Fig. 2, is to use a New-
ton cutting-off machine having an air clamp for holding
the bar in place while it is being cut off. A Hunter duplex
saw, as shown in the illustration, provided with high-speed
steel inserted teeth, performs the cutting operation. The
billet for an 18-pound shrapnel shell is 31/2 inches in diame-
40
MACHINING AND HEAT-TREATMENT 41
ter by 4^ inches long. It is then forged to shape, as has
been previously explained.
Assuming that the forging has been completed, the fol-
lowing is a complete summary of the machining operations
on the shell up to the point of assembling. In one plant
where this work is being done, the shrapnel shells are
put through in lots of 120, each lot being kept in three
boxes, forty shells to a box. Out of every 120, one shell
after heat-treatment is tested for tensile strength. The
tensile strength before heat-treatment must be from 30,000
to 40,000 pounds per square inch, and from 80,000 to 90,000
Fig. 2. Cutting off Billets for making Shrapnel Forgings in a
Newton Cutting-off Machine
pounds per square inch after heat-treatment. For facili-
tating transportation, trucks of various designs are used.
One type of truck used for this purpose is shown in Fig. 3.
This is built by the Chapman Double Ball Bearing Co. of
Canada, Ltd., Toronto, Ontario, and has some interesting
features, the chief of which are the ball-bearing swiveling
head, ball-bearing wheels, and the means of releasing or
raising the load with the handle in any position. This
feature is valuable in using the truck in a crowded space.
Trimming and Facing the Shell Forging. The first ma-
chining operation on the forged shell is to cut off the rag-
42
MACHINING AND HEAT-TREATMENT
ged end, which is generally from i/ 2 to li/ 2 inch longer
than that required for the finished shell. This operation
is performed in many different ways, but one of the most
common is to place it in a Hurlbut-Rogers cutting-off
machine as shown in Fig. 4. For performing the cutting-
off operation, two plain forged cutting-off tools made from
"Sabine" extra high-speed steel are used. The forging is
located in the proper position in the chuck by a plunger or
stop A, sliding in a fixture B clamped to the base of the
machine. This plunger locates the shell from the bottom
of the hole or powder pocket and forces the shell into the
Fig. 3. Truck built by the Chapman Double Ball Bearing Co.
for transferring Shrapnel Shells about the Shop
chuck against the resistance of an open-wound spring. The
stop is then located by a gage C that forms a member of
the fixture and fitting ring D on the stop. The chuck jaws
are now clamped on the work and the cutting off com-
mences. As soon as the excess stock is cut off, the stop
is drawn back and the pressure of the jaws on the work
released; the spring in the chuck then ejects the forging.
The production of an 18-pound shell from one machine is
about 140 in eight hours.
The next roughing operation is to face off the bottom or
closed end of the forging, bringing the shell to approxi-
MACHINING AND HEAT-TREATMENT
43
mately the correct length. There are also many ways of
performing this operation. One method is to grip the forg-
ing in a chuck, as shown in Fig. 5, in an ordinary lathe
and face off the end with a high-speed steel tool held in an
Armstrong tool-holder. From 14 to % inch is faced off
from the end.
Fig
Cutting off Excess Length of Shrapnel Forging in
Hurlbut-Rogers Cutting-off Machine
Fig. 5. Facing off Closed End of Shell to Length
Rough-turning Operations on Shrapnel Forging. Prac-
tically every type of engine lathe and turret lathe as well
as special machines are used for turning and boring shrap-
nel forgings, and in the following chapter each method
will be dealt with separately. Before doing this, however,
34 MACHINING AND HEAT-TREATMENT
a complete summary of the methods of machining employed
in a large plant turning out shrapnel will be described.
In this plant, the first rough-turning operation is handled
on a flat turret lathe, as shown in Fig. 6. For this purpose,
the shell forging is held on an expanding arbor and is
driven by a dog fastened to it and driven by the faceplate
of the lathe. A multiple tool turner is first brought into
position and takes a cut of about % inch from the diame-
ter for practically the entire length of the shell. The next
tool then faces off the end of the shell to length.
Fig. 6. First Rough-turning Operation on Shrapnel Shell
in a Flat Turret Lathe
The shell forging is now ready for cutting the rifling
band groove and producing the waves. This is handled in
an ordinary engine lathe equipped with a special fixture,
carrying grooving, waving and under-cutting tools. The
shell forging, as shown in Fig. 7, is held in a chuck at
one end and supported by a revolving center at the other.
One part of the fixture is clamped to the bed of the lathe
and the other to the carriage. The grooving and ribbing
is accomplished with a tool held in holder A at the front
of the lathe, whereas the two under-cutting tools are held in
holders D and E at the rear of the lathe. In operation
the carriage of the lathe is moved toward the chuck, carry-
MACHINING AND HEAT-TREATMENT 45
ing the fixture to which are fastened cams C, F, and G.
Cam C forces in the holder carrying the combination groov-
ing and ribbing tool, whereas cams F and G force in the
holders carrying the two under-cutting tools, these being
presented at an angle to the work. The required oscilla-
tions to the slide carrying the grooving and ribbing tool
are secured through a face-cam B clamped to a "Whiten"
chuck. The face-cam operates against the tension of
spring H and gives the required oscillations to the tool-
slide carrying the ribbing and grooving tool, shown at A.
The third machining operation is accomplished in a flat
turret lathe, as illustrated in Fig. 8. This consists in fac-
Fig. 7. Cutting the Rifling Band Groove with a Special
Grooving and Ribbing Attachment on an Engine Lathe
ing the open end of the shell, boring the powder pocket and
facing and boring the diaphragm seat, and also turning
the angular surface on the external nose of the shell. First,
a roughing drill is brought in to rough out the powder
pocket. The turret is then indexed and a tool for turning
the angle of the nose is brought into position. The machin-
ing on the nose is then accomplished by operating the cross-
sliding head. Then a roughing cutter is brought in to
rough-bore the powder pocket. The turret is again indexed
and a finishing tool is brought in to finish the powder pocket
and face the diaphragm seat. This finishes the machining
operations on the shell previous to heat-treatment.
46
MACHINING AND HEAT-TREATMENT
Fig. 8. Third Machining Operation on Shrapnel Shell in a Flat Turret Lathe,
consisting in Facing the Open End of the Shell, Boring the Powder
Pocket, Facing and Boring the Diaphragm Seat, and Turning
the Angular Surface on the External Nose of the Shell
Fig. 9. Heat-treating Shrapnel Shells, using a Hoskins Electric
Barium-chloride Bath Furnace
MACHINING AND HEAT-TREATMENT 47
Heat-treating Shrapnel Shells. As was previously stat-
ed, the tensile strength of a forged shrapnel shell after
heat-treatment must be from 80,000 to 90,000 pounds per
square inch, and in order to obtain the desired physical
qualities, it is necessary that the heat-treating operations
be properly conducted. Several methods of heat-treating
employing different cooling solutions are used in the manu-
facturing plants making shrapnel shells. One method, as
Fig. 10. Testing Hardness of Shrapnel Shells with
Shore Scleroscope
shown in Fig. 9, is to heat the shell in a Hoskins electric
furnace that contains a barium-chloride bath, heated to a
temperature of about 1480 degrees F. The shells are left
in this furnace for half an hour and are taken out and
dipped in a bath of cotton-seed oil heated to a temperature
of 113 degrees F. The temperature to which the shell is
heated varies with the different constituents of the steel
and practically every different batch of 120 shells requires
48 MACHINING AND HEAT-TREATMENT
a slightly different temperature. The proper temperature
is determined by cutting out a section of a heat-treated
shell and testing it for tensile strength. The next step is
to draw the temper on the open end of the shell. In this
operation a muffle gas furnace heated to a temperature of
about 1000 degrees F., is used. The temper is drawn for
about two-thirds of the length of the shrapnel shells.
Testing for Hardness and Tensile Strength. One shell
from a batch of 120 is now cut open in the proximity of
the powder pocket and the cut-out section sent to the gov-
ernment inspectors to test it for tensile strength. Each
one of the shells in the batch, in addition, is tested for
hardness by a Shore scleroscope as shown in Fig. 10. Be-
fore testing for hardness, the shell near the band groove is
polished so as to get a true reading, then placed in a fixture,
and the hammer of the scleroscope allowed to drop on it.
The reading should be between 40 and 50, indicating an
elastic limit of from 80,000 to 90,000 pounds per square
inch. The shell must not be ruptured at the point tested
when the charge in it is exploded or when the charge in the
case is set off. Should the shell upset near the rifling band
groove when it is propelled out of the gun, it would tear
out the rifling in the bore of the gun.
Experience with the scleroscope has disclosed the exist-
ence of a fairly definite relation between the hardness and
strength of metal. In determining the strength of metal,
two stages are recognized: First, the elastic limit, deter-
mined by the load required to produce a permanent set;
second, the ultimate strength, determined by the load re-
quired to cause rupture. The hardness indicated by the
scleroscope is intimately related to the elastic limit. The
elastic limit increases more rapidly than the hardness from
43 to 45, this being the minimum index of the strength value
required. As an elongation of 8 per cent in 2 inches is
also required, there must necessarily be an upper limit to
the hardness. On the steel used for shrapnel, which is
generally about 50-point carbon and 60-point manganese,
the maximum hardness should not be over 60 on the
scleroscope.
MACHINING AND HEAT-TREATMENT
49
Tests relating to Heat-treatment of Shells. In the
September, 1915, number of MACHINERY, Mr. J. M. Wilson,
who has been actively engaged in heat-treating shells since
the beginning of the war, and who has had to rely entirely
upon his own resources in meeting and overcoming the
troubles which seemed to arise on all sides, relates the
results of his experiments.
The British government shell specifications call for a
yield point or elastic limit, after heat-treating, of not less
than 36 tons per square inch, a breaking point or ultimate
Machinery
Fig. 11. Cross-sectional View of Shrapnel Shell showing Points
A, B, and C where Tests are made, and one of the
Tensile Test Samples
strength not less than 56 tons per square inch, and an
elongation not less than 8 per cent in % inch. Officially
there is no maximum specified for either of those three
physical characteristics ; but as a matter of fact any unus-
ual condition which is not in conformity with recognized
metallurgical practice may cause the chief government in-
spector for the district in which the manufacturer is located
to reject a shipment. Reference has been made to certain
points in the shell which must resist the strains due to
firing. The nature of these strains and condition of the
steel best suited to meet them will be understood from
Fig. 11, which shows a cross-section of the British 18-
pound shrapnel shell. When a shell is fired from a gun,
the base A is subjected to a blow, i. e., a sudden increase
of pressure which almost instantly attains a maximum of
from 12 to 14 tons per square inch, and imparts the initial
velocity to the shell. The shell, being a body at rest, op-
50 MACHINING AND HEAT-TREATMENT
poses this velocity with its own inertia, the result being
that both compressive and tensile strains are set up in the
shell body. The shell body assumes the conditions of a
column which has a compressive load varying from noth-
ing at the nose to a maximum at the base. The tensile
load is due to the inertia of the bullets inside the shell.
These bullets are subject to an increasing compressive load
from the top down, the resultant strain being a bursting
effort which attains a maximum in the region of the point
B, known as the "set-up point."
When the time required for the fuse to act has elapsed,
the powder charge is exploded, and the contents of the shell
are blown forward in the usual manner. The contents are
released either by the stripping of the thread of the brass
socket, or else the walls of the shell yield at the point C,
opening the threads sufficiently to free the socket. At A,
(the base) the shell must be perfectly sound and free from
flaws such as minute cracks, etc., which may allow the
flame from the firing charge to strike through with disas-
trous results to the shell and gun. The metal in the base
must not be too hard or it may fracture under the pressure
of the explosion, and it must not be too soft or it may
flatten out and spoil the rifling in the bore. At the point B
there is no maximum requirement so far as tensile strength
is concerned, but any abnormal strength is viewed with
suspicion unless it is accompanied by a generous elongation.
At B the metal is particularly liable to distension while the
shell is acquiring velocity, and unless the shell is strong
enough to resist the sudden bursting strain, and the amount
of elongation is sufficient to cushion or absorb this strain at
the instant of firing, the shell is liable to take a permanent
set in the region of point B, with results mentioned above,
The shell must not be too hard at the point C as it may
burst, thus neutralizing the real object of a shrapnel shell
which is to project the bullets forward with increased
velocity at the predetermined instant, being in fact an aerial
gun arranged to discharge its contents at any desired point
of its flight.
MACHINING AND HEAT-TREATMENT 51
Uniformity of Steel for Shrapnel. Having these re-
quirements firmly established in his mind, the heat-treating
expert is now confronted with a double problem: How
is it possible to give steel the suitable strength ; and having
done so, how is it possible to know that the desired result
has been obtained, without actually making test pieces from
each shell. The principal condition upon which successful
heat-treating depends is uniformity of material. Carbon
and manganese are the principal substances which influence
the results. The exact composition of steel specified by
the government is not given to any manufacturers other
than steelmakers. It is, however, generally understood to
be a 0.50 per cent carbon, 0.60 per cent manganese steel.
Allowing five points variation in carbon and ten points
variation in manganese, the requirements would be ap-
proximately 0.45 to 0.55 per cent carbon and 0.50 to 0.70
per cent manganese. In one carload of forgings, one firm
received shells from 23 different heats or melts, with carbon
varying from 0.60 to 0.47 per cent, and manganese varying
from 0.63 to 0.49 per cent, with all possible combinations
and proportions between these limits. The number of
forgings supplied from each heat varied from one up to
1200 so that the question of determining the best tempera-
ture for each carbon content was indeed quite impracticable.
Many manufacturers at the present moment may be in a
similar position, and the gravity of the situation, both from
a financial and a military point of view, may justify a
somewhat detailed description of the method which was
followed in treating shells of such varying composition.
Results of Tests. It is generally known to manufac-
turers that the highest tensile strength of steel is obtained
by cooling it rapidly from a temperature slightly higher
than the decalescent point or critical temperature. The
degree of hardness resulting from this operation can be
ascertained quickly, accurately, and repeatedly by means
of the scleroscope. The degree of hardness thus shown is
a reliable indication of the probable strength of the mate-
rial; that is to say, after making due allowance for differ-
ent makes of steel and varying proportions of the principal
52
MACHINING AND HEAT-TREATMENT
constituents, the scleroscope readings are a reliable indica-
tion of the results which may be expected when a tensile
test is made of any given shell. In the opening months of
the shell business, considerable reliance was placed on the
accurate determination of the decalescence point. Forg-
ings of varying analysis were received; the carbon being
from 0.48 to 0.53 per cent, and the manganese from 0.54 to
0.69 per cent. All steels whose composition was within
those limits showed a decalescence point of between 1390
and 1425 degrees F., and when quenched in water at 50
degrees F. above the decalescence point, such steels would
have a scleroscope hardness number as high as 85; but
when quenched in ordinary fish oil the hardness was only
slightly over 50, the sample being 1 inch square and Vs
TABLE I. RESULTS OF TESTS TO DETERMINE THE BEST QUENCHING MEDIUM
FOR SHRAPNEL SHELLS
Quenching
temperature,
degrees F.
Quenching
medium
Temperature of
quenching
medium, degrees F.
Scleroscope
hardness No.
1475
Fish oil
90
50 to 55
1475
Coal oil
90
65 to 70
1475
1475
1475
1475
Cottonseed oil..
Engine oil
Oil of degras . .
Water
90
90
90
90
70 to 75
75 to 80
77 to 85
82 to 87
Machinery
inch thick. A complete shell quenched in fish oil would
show a scleroscope hardness number at the set-up point of
from 38 to 40. Test pieces from such a shell failed to reach
the minimum breaking strength of 56 tons by the narrow
margin of 0.6 ton, and this failure brought up the ques-
tion of which was the best quenching medium. A series
of experiments gave the results presented in Table I; all
conditions were equal in each test, and the test pieces were
all made from the same forging.
From the results of the tests presented in Table I, oil of
degras, commercially known as "No 2 soluble quenching
oil," was selected as the quenching medium and operations
were commenced on forgings supplied from two separate
heats. The results were all that could be desired until
MACHINING AND HEAT-TREATMENT
53
forgings were received from a certain heat, which would
not respond to treatment based upon the results of pre-
liminary experiments. Investigation yielded the results
presented in Table II. While water-treatment of the forg-
ings from "Heat No. 3" gave satisfactory strengths under
test, the liability of shells to crack, owing to their thin
TABLE II. RESULTS OF TESTS CONDUCTED TO SECURE GENERAL DATA
01T HE AT- TREATMENT
Heat No.
i
2
3
Carbon per cent
45
52
50
Manganese, per cent...
Decalescent point, de-
grees P
0.68
1400
0.62
1425
0.47
1390
Quenching temperature,
degrees F ....
1450
1475
1450
Temperature of oil,
degrees P ....
160
160
120
Resultant hardness,
scleroscope No
65 to 75
65 to 75
*39
Temperature of water,
degrees F
75
Resultant hardness,
scleroscope No
Tempered until show-
in g a scleroscope
hardness of
48
48
55 to 60
52
Yield point tons
47 8
48 6
46 5
Breaking point, tons...
Elongation, per cent...
67.9
14.5
65.4
16.9
66.2
17.4
Machinery
*Note: This shell was then reheated and quenched in water with results shown.
walls contracting more rapidly than the base, was a fatal
objection to this method. Attention should be called to the
fact that while the temperature at which quenching should
be done is specified by the government at 1560 degrees F.,
manufacturers are not tied down to this particular tem-
perature. What is required is that the manufacturers shall
so treat the material that it will fulfill the requirements
54
MACHINING AND HEAT-TREATMENT
already stated. If, when fulfilling these requirements, the
treatment should prove detrimental to the shell in other re-
spects, then it must be changed accordingly.
Referring to results presented in Table II, "Heat No. 3,"
it will be observed that the manganese is only 0.47 per
cent with carbon 0.50 per cent. Comparing "Heat No. 3"
with "Heat No. 1", it is evident that an increase of 5 points
carbon is more than -offset by a reduction of 21 points in
the manganese. Increase of temperature seemed to offer
the greatest possibilities and sample shells were drawn
every 121/2 degrees up to 1675 degrees F. The greatest
hardness was obtained at 1637^, scleroscope readings of
from 50 to 55 being the average. This was not considered
TABLE III. RESULTS OF TESTS ON SAMPLES TAKEN FROM A SHELL WITH A
SCLEROSCOPE HARDNESS NUMBER OF FROM 48 TO 52
Heat No.
Scleroscope reading on
test piece after ma-
chining
Yield Point,
tons
Breaking
point, tons
Elongation,
per cent
1
Outside 525350 )
Inside 555555 f
55.8
73.3
14.3
2
Outside 525450 )
Inside 555753 j"
53.8
72.4
17.4
3
Outside 575749 /
Inside 606251 V
52.8
77.3
12.7
Machinery
satisfactory, and the oil-circulating pump was speeded up.
Scleroscope readings as high as 65 were frequently obtained
at a quenching temperature of approximately 1635 degrees,
and when the shell was tempered to read 48 to 52 on the
scleroscope, three test pieces from one shell gave the results
presented in Table III. A careful study of this data re-
vealed the fact that, while a low-carbon, low-manganese
steel hardens satisfactorily within a limited range of tem-
perature, a medium steel has a wider range, and a high-
carbon steel, a still wider range of hardening temperature.
When the shipment of mixed heats previously referred
to was treated, the method pursued was to take 0.50 per
cent carbon and 0.50 per cent manganese as a base compo-
sition which hardened at 1600 degrees F. to show 55 to 65
MACHINING AND HEAT-TREATMENT
55
hardness on the scleroscope. Then : (a) If, for every point
of carbon below 50, there be present 1 or more points of
manganese above 50, the steel should harden satisfactorily
at 1600 degrees F. (b) If, for every point of manganese
below 50, there be present 2 or more points of carbon above
50, the steel should harden satisfactorily at 1600 degrees
F. (c) If both carbon and manganese be below 0.50 per
0.45
ACTUAL LIMITS OF MANGANESE, PER CENT
Machinery
Fig. 12. Chart showing Hardening Temperatures for Various
Percentages of Carbon and Manganese in Steel used for
Shrapnel Shells
cent, increase the hardening temperature 12% degrees F.
for each point of manganese short of 50, and 6*4 degrees
F. for each point of carbon short of 50. (d) If both carbon
and manganese are above 0.50 per cent, a hardness number
above 55 will probably be obtained at a quenching tem-
perature of 1600 degrees F., but the maximum hardness,
56 MACHINING AND HEAT-TREATMENT
i. e., from 75 to 80, will be obtained at a somewhat lower
temperature, the exact temperature being most easily found
by starting at 1500 degrees F. and trying a couple of sam-
ple shells every 25 degrees F. until a maximum hardness
is obtained. Forgings containing from 0.50 to 0.55 per
cent carbon and from 0.54 to 0.62 per cent manganese in
any varying proportions may be hardened at 1600 degrees
F. to show a hardness number of from 55 to 75 ; and when
tempered to give a hardness number of from 48 to 52 they
will yield the following results: yield point, 45 to 50 tons;
breaking point, 65 to 70 tons ; and elongation, 14 to 20 per
cent.
Looking back, (c) offers a basis for charting the harden-
ing points in a fairly approximate manner, to form a guide
as to where the best hardness may be obtained. Such a
chart is shown in Fig. 12. By following the horizontal
and vertical lines from the carbon and manganese content
until they intersect, a diagonal line will be found which
will indicate the temperature at or about which the maxi-
mum hardness will be obtained. This does not prevent the
use of 1600 degrees F. as the average temperature for the
majority of shells, provided they are strong enough when
hardened at that temperature; but where shells do not
harden satisfactorily at 1600 degrees F., the chart offers
an alternative method subject to such variation as may
arise due to the use of steel from different makers, etc.
Probably the best practice is to make careful scleroscope
readings of each piece before pulling. Care must be taken
to have a uniform surface on both sides, all tool marks be-
ing removed with fine emery cloth. The points tested are
shown at A, B, and C in Fig. 11. After the test piece is
made, the value of the hardness number increases as a
result of the piece being solidly supported in the scleroscope,
whereas, when the reading is made on the shell, the arched
form of the wall acts as a spring, and absorbs the shock
to some extent. Readings thus increase from 2 to 10
points after the test piece is finished.
A careful study of the data presented in Table IV re-
veals the fact that results are not always consistent. With
MACHINING AND HEAT-TREATMENT
57
TABLE IV. DATA ON THE HEAT-TREATMENT AND STRENGTH TESTS
OF SHRAPNEL SHELLS
Car-
bon,
per
cent
Manga-
nese,
per
cent
Quen-
ching
temper-
ature,
degrees
Tem-
pered,
sclero-
scope
hard-
ness
No.
Readings of
scleroscope
Yield
point,
tons
Break-
ing
point,
tons
Elong-
ation,
per
cent
0.50
0.47
1635
51
60 57^-57
474848
48.3
69.9
16.9
Three pieces from one shell
605653
485258
45.2
70.6
19.1
63^5657
515554
51.6
74.6
16.9
0.48
0.65
1565
49
515452
485350
47.3
67.4
15.9
Three pieces from one shell
515249
535151
48.2
67.9
15.3
525550
505547
49.2
70.7
15.4
0.50
0.57
1600
50
505250
495049
46.0
64.8
19.0
0.50
0.57
1600
60
566057
545654
55.8
77.8
14.3
0.50
0.57
1600
50
596056
5559+56
60.7
82.2
12.7
0.60
0.57
1600
60
606155
606257
57.8
80.0
12.6
0.60
0.57
1600
52
575756
545653
48.2
69.7
17.5
0.50
0.57
1600
50
485250
495249
44.2
64.3
17.4
0.50
0.57
1600
50
525555
605152
44.7
65.2
14.7
Machinery
an increase of carbon, one occasionally finds an increase in
elongation and vice versa; and the results due to variations
in manganese content are similarly unreliable. In order
to secure a degree of uniformity in hardness, which will be
sufficient to insure test pieces standing up successfully, it
is necessary to have the shell hard inside as well as outside,
and a method of doing this is referred to later. Assuming
now that the shell has been tempered, it is rough-polished
58
MACHINING AND HEAT-TREATMENT
*J siLLJ i
MACHINING AND HEAT-TREATMENT 59
on a canvas buffing wheel around the outside of B, Fig.
11, for a width of at least 1 inch. Readings by the sclero-
scope are made on a zone % inch wide, and if they are
between 46 and 52 the shell may be relied upon to show
good results in the tensile test. In making test pieces, it
is desirable to cut the piece from a spot which reads 48
to 50 ; and in machining the test piece, care should be taken
to remove an equal quantity of metal from either side of
the wall so that the test piece is a true specimen of the
average wall structure. Where a shell is carelessly
quenched, and the test piece so machined that the surface
on one side is practically the same as the inner side of
the wall, the results would not be a true indication of the
real average strength, and a lot of shells might possibly
be rejected on account of a slight oversight in this respect.
Reference has been made to the base A, Fig. 11. Forging
defects show up here occasionally and in such cases the
shell is at once condemned. These flaws take the form of
small cracks, from the width of a hair up to 1/16 inch.
They seldom can be detected until after heat-treating, and
are most easily observed by polishing the base on a disk
grinder. Losses in this respect vary, but might average
about 0.20 per cent. The hardness of the base itself may
vary from 38 to 50, which insures an ample degree of
toughness and avoids all possibility of the shell cracking
under fire.
Heat-treating Department. Many methods of heating,
quenching, annealing, and cleaning are in use by the
different firms engaged in shell making. For rapidity of
output, cleanliness of the resulting product, ease and econ-
omy of operation, and uniformity and control of results,
the lead bath seems best for hardening, and the semi-muffle
furnace for annealing. In one case the use of a lead bath
by a skilled operator yielded excellent results both as to
economy and uniformity, but, when the output exceeds
500 shells per 12 hours, a semi-continuous furnace meets
the requirements to better advantage. The lay-out of a
hardening room for an output of 12,000 shells per week
is given in Fig. 13. The lead baths consist of a rectan-
60
MACHINING AND HEAT-TREATMENT
gular pot of suitable capacity, resting on a 4i/2-mch hearth
built of common firebrick and heated by either oil or gas
burners below the hearth. They are built in pairs with
a common wall between, which is thick enough to provide
a flue to carry off products of combustion. The quenching
tanks are rectangular, water- jacketed, and provided with
two quenching cradles each. These cradles are arranged
to swing lengthwise in the tank, and, when the carrier hold-
MacMnery
Fig. 14. Special Arrangement of Scleroscope for Testing
Shrapnel Shells
ing the shell is lowered into the oil, a pipe is automatically
extended downward into the shell and introduces cold oil
in the inside of the shell, while the operator swings the
cradle back and forth in the tank, thus cooling the outside
of the shell at the same time. This method of quenching
made it possible to harden shells which, by reason of low
carbon and manganese, defied all conventional methods of
dipping and swinging back and forth with tongs. The
MACHINING AND HEAT-TREATMENT
61
output per man with this apparatus is largely in excess of
any hand method, while the uniformity and degree of
hardness is all that could be desired.
The oil pump draws the oil from a depth of 6 inches
below the surface and pumps it through 100 feet of 1-inch
copper pipe arranged in two 50-foot coils in parallel. The
cooled oil is delivered into an overhead reservoir, the over-
flow being connected to both tanks equally. After quench-
ing, the shells are set on draining racks, and then washed
in boiling water and sal-soda, placed on another draining
rack and then brushed with wire brushes previous to
tempering. The tempering furnace is of rectangular form,
Fig. 15. Closing in Nose of Shrapnel Shell in Hydraulic Press
and consists of a long flat hearth with rails laid lengthwise
on it. At each end a space is partitioned off from the
body of the furnace, by means of vertical sliding doors;
and a rack holding a number of shells is deposited on the
rails at the front end of the hearth, the door is elevated
and the rack is slid into the main chamber. After a suita-
ble lapse of time another rack is introduced, and so on until
the first rack is ejected at the rear end of the furnace. The
shells are now hot enough to loosen all foreign matter on
the surface, and a few seconds brushing with a wire brush
cleans out the driving band groove, and leaves the shell
62
MACHINING AND HEAT-TREATMENT
with a delicate brown oxidized finish. The shell is now
spotted on three places with a canvas buff and tested for
hardness. Fig. 14 shows the arrangement of the scle-
roscope. The shell is supported on a single narrow
V-block with hardened edges, situated immediately under
the set-up point. A narrow strip supports the open end
of the shell, thus giving a three-point support, while a ver-
tical stop at the back of the shell maintains it in a position
tangential to the radius of the swinging arm. The usual
rubber bulb was soon dispensed with as being quite unsuited
Fig. 16.
Third Operation on Nose of Shrapnel Shell Turning, Facing,
and Threading
for such hard service, and a small pump cylinder substi-
tuted. The piston in the cylinder is operated by a down-
ward pressure of the heel on the pedal to give compression,
and a spring inside the cylinder gives the necessary pull
when the scleroscope hammer is to be raised by suction.
After being tested the shells are ready for "nosing in."
Closing-in the End of the Shell. On some makes of
shells, particularly the British, the nose is closed in before
performing the third series of machining operations. The
closing-in is generally accomplished in a hydraulic or power
MACHINING AND HEAT-TREATMENT
63
Fig. 17. Grinding Shrapnel Shells In One Operation Fn a Ford-Smith Grinding
Machine carrying a Wheel about 8^ Inches Wide by 20 Inches In
Diameter, rotated at 1200 Revolutions per Minute
Fig. 18. Closing in Copper Band on Shrapnel Shell in a Machine provided
with Six Dies, as shown in Fig. 20, back of each one of which
there is a Hydraulic Cylinder ,
64
MACHINING AND HEAT-TREATMENT
press. Fig. 15 shows the closing-in operation being per-
formed in a vertical hydraulic press capable of exerting a
pressure of 800 pounds per square inch. Before closing
the open end of the shell, it is heated in the lead bath,
shown to the left of the illustration, which is kept at a
temperature between 1450 and 1500 degrees F. The steel
diaphragm, which is larger in diameter than the nose of
the shell, is first thrown in. Then the shell is placed in
the press, and a cone-shaped die descends, closing in the
nose to the proper shape and diameter. The third machin-
ing operation consists in finishing the radius on the nose,
both inside and outside, and cutting the thread. This is
Machinery
Fig. 19. Special Type of Wheel-truing Device used on Ford-Smith
Grinding Machine shown in Fig. 17
done, as shown in Fig. 16, in an ordinary engine lathe with
a turret on the saddle. The boring is done with cutters
held in boring-bars and the thread cut with a Geometric
collapsible tap. The thread on the 18-pounder is 2.94
inches in diameter, 14-pitch, Whitworth type.
Grinding Shrapnel Shells. The exterior surface of a
shrapnel shell is straight for a portion of the length and
then curved on the nose. While the limits required are
not extremely close, it is necessary, where large production
is required, to accomplish the finishing operations on the
exterior of the shell in some way by which fairly close
MACHINING AND HEAT-TREATMENT 65
dimensions can be secured as well as large production.
Grinding has, therefore, been recommended for finishing
the exterior of the shell. One method of grinding shrapnel
shells, in which a wide-faced wheel is used that covers the
entire ground surface, is shown in Fig. 17. This machine
is built by the Ford-Smith Machine Co., Hamilton, Ont.,
and carries a wheel about 8*4 inches wide by 20 inches in
diameter. The grinding wheel is rotated at 1200 R. P. M.,
and the work at 50 R. P. M. The depth of the cut is
about 1/32 inch, and the time to complete one shell varies
between two and three minutes. For grinding, a plug is
Fig. 20. Close View showing Closing-in Dies of Banding
Machine shown in Fig. 18
screwed into the open end of the shell. This is held on
the tailstock center and a chuck holds and drives the shell
from the other end.
It is necessary, of course, that the wheel be kept the
correct shape, and for this purpose an interesting type of
wheel-truing device, differing considerably from that shown
in Fig. 17, is now used. Referring to Fig. 19, it will be
seen that this comprises a combination wheel guard and
bracket, the latter being used as a base for the wheel-truing
device proper. The diamond A is carried in a holder B
that operates in a slide in the face of the traversing wheel-
truing slide C. The diamond holder carries a cam point
66 MACHINING AND HEAT-TREATMENT
D which is kept in contact with the guide or former cam E
by means of a spring F. The wheel-truing slide C is tra-
versed by a triple pitch screw G so as to give a rapid move-
ment to the slide in order to produce what might be termed
a "rough-truing" of the wheel. For change in diameter,
and also for bringing the diamond in contact with the wheel,
a vertical slide H is provided that is operated by handle /.
In order to observe the diamond when truing the wheel, a
trap door J is provided in the wheel guard, which can be
dropped down into place when the actual grinding of the
shell is being done.
Pressing on the Rifling Band. In order to rotate the
shrapnel when propelling it out of the howitzer, it is nec-
essary to put on a rifling band to take the rifling grooves
of the gun bore. As a rule, these rifling bands are made
from copper tubing and are simply cut off in a hand screw
machine or turret lathe. The next operation is to close in
the rifling band on the shrapnel shell. The ring is dropped
over the shell and a fixture is used to locate it in the correct
relation to the groove in the circumference of the shell.
Then a slight pressure is exerted on it to align it properly
in the groove. It is now placed in the banding machine
shown in Fig. 18. This particular machine is provided
with six dies as shown in Fig. 20, and back of each one is
a hydraulic cylinder operated by water pressure. Two
squeezers are necessary to close the rifling band properly
into the groove, the shell being given a half turn after each
squeeze.
There are several different machines on the market for
performing this closing-in operation on the rifling band.
Another machine, built by the West Tire Setter Co., Roches-
ter, N. Y., is shown in Fig. 21. The principle upon which
this machine operates is almost identical with that pre-
viously described, but in this case oil is used as a pressure
medium. It is forced into the machine by means of a belt-
driven pump shown to the left of the illustration, which
drives the oil from the oil tank and carries it to the center
of the base of the press. An oil head is located at this
point from which the pipes are run to each of the six rams
MACHINING AND HEAT-TREATMENT
67
Fig. 21. Shrapnel Banding Machine built by the West Tire Setter Co.,
having a Capacity for Compressing two Bands per Minute
Fig. 22. Assembling Bullets, Resin, and Fuse Socket in Shrapnel Shell
68 MACHINING AND HEAT-TREATMENT
or cylinders. The amount of pressure required for com-
pressing the copper band depends largely upon the width
and thickness and the amount that the band must be spread
to fill the grooves, rather than upon the diameter of the
shell. The machine shown in Fig. 21 is capable of exerting
a pressure of 30 tons on each cylinder or a combined pres-
sure of 180 tons on all six cylinders. It has a capacity
for compressing at least two bands per minute.
Machining the Rifling Band. One method of machin-
ing the rifling band to the correct shape is shown in Fig.
Fig. 23. Finishing Rifling Band on Shrapnel Shell to Shape
23. Here a Fox lathe is used which is provided with a
chuck for holding the shell and which carries in the turret
a revolving center for additionally supporting it. The ma-
chining is done by form tools which are of the correct
shape. Before any other machining operations can be ac-
complished it is necessary to put in the tin powder cup,
brass fuse tube, bullets, and resin. This cup is slipped
in past the steel diaphragm, then both parts are allowed
to drop to the bottom and the fuse tube is screwed into
the diaphragm. The required number of lead bullets, which
70
MACHINING AND HEAT-TREATMENT
for the British 18-pound shrapnel is about 375 per shell,
is then poured in. The bullets are held in a tank and are
allowed to flow out upon the opening of a stopcock. In
order to pack the bullets solidly, a compressed air ramming
device forms the base upon which the shell rests while the
bullets are being poured in. This is operated three or four
times for the filling of each shell and arranges the bullets
compactly.
The resin is now poured in, as shown in the center of
Fig. 22. This is carried in the tank which is heated by
a gas furnace and is poured in almost level with the top of
the bullets. The shell is then placed on the scale in the im-
mediate foreground and weighed. One dram plus or minus
is allowed as a variation, and in order to not exceed this,
Fig. 25. 18-pound Shrapnel Shell showing Dimensions and
Manufacturing Limits
more or less resin is poured in until the correct weight is
obtained. The brass fuse socket is now screwed in as
shown to the left of the illustration, and upon the comple-
tion of this operation the shell is ready for the fourth and
last machining operation. This last operation consists in
machining the brass socket on the outside diameter to con-
form to the radius on the nose of the shell, and boring on
the inside and threading to fit the fuse body. These oper-
ations are handled in a Fox brass working lathe. Upon
the completion of the machining operations the plug is
screwed in, the shell stamped, cleaned, weighed, and in-
spected by government inspectors. After this, the shell is
given two coats of paint and a red band is painted around
the nose. It is now packed in boxes holding six shells
MACHINING AND HEAT-TREATMENT
71
Fig. 26. Group of Gages made by Wells Bros. Co. for gaging
British Shrapnel Shells and Parts
and is ready for shipment. This completes the manufac-
ture of the shrapnel shell.
Gaging Shrapnel Shells. The machining operations on
shrapnel shells are required to be held within certain limits,
and government inspectors watch these closely. Some of
the principal gaging operations on the shrapnel shell body
Machinery
Fig. 27. Diagram showing Application of Wells Bros. Gages
72
MACHINING AND HEAT-TREATMENT
Fig. 28. Collection of Wells Bros. Co.'s American Shrapnel Shell Gages
are shown in Fig. 24. Fig. 25 shows the 18-pound shrapnel
shell in section, and gives the principal dimensions together
with the limits ; it will be seen from this illustration that the
range allowable is in most cases large. The Wells Bros.
Co., Greenfield, Mass., has made a large number of shrapnel
gages, some of which are shown in the accompanying illus-
trations. In the three upper views of Fig. 24, the Wells
Bros, standard thread gage is illustrated. This is used
for all diameter measurements by substituting flat gaging
pins for the V-points used when gaging thread diameters.
Gages for British Shrapnel Parts. Fig. 26 illustrates
typical gages for gaging such parts of the British shrapnel
Fig. 29.
Dwight-Slate Hand-operated Marking Machine
for Shrapnel Shells
MACHINING AND HEAT-TREATMENT
73
as body diameters, diaphragm seat, powder pocket, fuse
socket, thread diameters, and fuse parts. Fig. 27 shows
the application of several different types of shrapnel shell
gages. At A is the gage for the over-all length. At B is
the gage used for measuring the thickness of the closed
end. The outer arm of this gage can be swung away to
allow the placing of the gage on the standard. At the
extreme lower left-
hand corner of the
gaging arm is a slight
shoulder on the rod
and the height of this
acts as the limit. C
shows the application
of outside diameter
and thread gages. D
shows three form
gages for checking the
shape and dimensions
of the wave ribs, the
diameter and shape of
the undercut i n t h e
band groove, and the
shape of the nose of
the shell. E shows
the gage used for
checking the thickness
of the wall of the shell
at different distances
from the mouth. F
shows the application
of a powder pocket gage, and also a gage for checking the
shape of the finished rifling band.
Gages for American Shrapnel Shells. Fig. 28 shows a
miscellaneous collection of gages used in checking the di-
mensions of the American shrapnel shell. Gages, A, B, C,
and D are for measuring the diameter of the diaphragm
seat. E is for checking the distance from the diaphragm
seat to the mouth end of the shell, and gage F is for the
Fig. 30. Power-driven Dwight-Slate Mark-
ing Machine for Shrapnel Shells
74 MACHINING AND HEAT-TREATMENT
outside diameter of the shell. Gage G is used for the
rifling band groove. Gages H and / are for the thread in
the mouth of the shell, H being a "not-go" and / a "go"
gage.
The gage at J performs several gaging functions on the
American shell. It consists of a standard having two up-
right posts across which a bar is mounted. The purpose
of the bar is to gage the over-all length of the shell, and its
lower surface is provided with two steps giving the limits.
This gage is also used for measuring the depth of the pow-
der pocket, rod K and block L performing this function.
Two rings are cut around the rod K registering with the
top surface of the bar, the purpose being to show the accu-
racy of the work.
Another interesting gage is shown at M. This is for
gaging the concentricity of the shell and consists of an
arbor mounted so that it can be swung on a pivot. The
arbor carries two collars N and O that fit in the shell.
Collar P is merely a sizing plug and when the gage is in
use this plug is removed. A gaging finger Q rests against
the shell when it is on this arbor, and a standard type of
indicator R shows the variation in concentricity when the
gage, collars, and shell are rotated on the arbor.
Marking Shrapnel Shells. All shrapnel shells are
marked on their circumference with five or six lines of
lettering, as shown in Fig. 29. This indicates the size of
the shell, the series, muzzle velocity, name of the manufac-
turer, date completed, etc. Two types of machines for
producing the stamping, built by Noble & Westbrook, Hart-
ford, Conn., are shown in Figs. 29 and 30. The machine
shown in Fig. 29 is of the hand-operated type. The figure
block A is held in a slide that is moved longitudinally by
pulling down handle B, rolling the shell, and at the same
time stamping it. The shell is located on the table in the
two positions by gages C and D.
The "Dwight-Slate" stamping machine shown in Fig. 30
is power-driven, and the work is held on an elevating table.
The stamp is held in a slide operated by an eccentric and
connecting-rod. In this machine the shell is not distorted.
CHAPTER IV
MACHINES AND TOOLS FOR SHRAPNEL MANUFACTURE
Reed-Prentice Co. Equipment for Machining Forged
Shrapnel Shells. In machining the 18-pound British
shrapnel shell on the equipment furnished by the Reed-
Prentice Co., Worcester, Mass., eight distinct operations
are performed as follows: First, drilling a center hole in
the closed end of the forging in a Prentice 16-inch ball-
bearing sensitive drilling machine equipped with a special
centering fixture ; second, rough-turning the outside diame-
ter, grooving, squaring the closed end and rounding the
corners in a Reed-Prentice 14-inch heavy type automatic
lathe; third, machining the powder pocket and diaphragm
seat, as well as the internal and external diameters of the
nose in a 14-inch Reed extra-heavy turret lathe; fourth,
under-cutting band grooves and producing wave ribs in a
14-inch Reed engine lathe; fifth, boring, reaming, thread-
ing and facing the open end in a Reed 14-inch extra-heavy
turret lathe; sixth, finish-turning outside diameter and
radius on nose, also form-turning copper band in a Reed
14-inch heavy type automatic lathe; seventh, cutting off
center projection on closed end of shell in a Reed 14-inch
engine lathe; eighth, finishing brass socket to form, clean-
ing inside of socket and cutting off excess length of tube
in a Reed 14-inch extra-heavy turning lathe.
First Operation on Rough Shell Forging. The drilling
of the center hole in the closed end of the forging is a
comparatively simple operation, and is performed in an in-
teresting fixture held on a 16-inch Prentice ball-bearing
sensitive drilling machine. This fixture, which is designed
for handling the work quickly, is shown in Fig. 1, and con-
sists of the base casting A clamped to the table of the drill-
ing machine. The entire back part of the jig swings on
the trunnion B to provide a means for quickly removing
the forging C from the arbor D. A locking pin E is used
for locating the fixture in its upright position for drilling.
75
76
SHRAPNEL MANUFACTURE
Machinery
Fig. 1. Fixtures used for holding Shrapnel Shell Forgings when
drilling Center Hole in a 16-inch Prentice Ball Bearing
Sensitive Drilling Machine
Bushing G in the top plate F of the fixture guides the
combination drill and countersink.
The construction of the work-holding arbor is worthy
of special attention. This arbor D has a cap H on its top
end that acts as a stop for the inside of the forging, which,
SHRAPNEL MANUFACTURE
77
in being placed over the arbor, is located centrally and
clamped by fingers N. To operate these fingers, hand lever
/ is depressed, and as this is fulcrumed at the point J, it
causes collar K to rise on the arbor. Yoke L forms a con-
nection between the lever and the collar with which the
sleeve carrying fingers N is integral. Fingers N are ful-
crumed in arbor D and are thrown outward to grip the
forging when sleeve M is raised. Light springs tend
to keep the gripping fingers in a vertical position against
Fig. 2. Tool Lay-out for performing Second Series of
Operations on Reed- Prentice Heavy Type
Automatic Lathe
the arbor when they are not being forced outward by the
inclined "surf aces on sleeve M. Handle / carries a spring
pawl P that holds the sleeve M stationary while the forging
is being center-drilled.
Second or Rough-turning and Facing Operations.
The second operation is performed on a Reed-Prentice
14-inch heavy type automatic lathe, as shown in Figs. 2
and 3. The forging A is held on an internal expanding
arbor B, the driving part of which is supported by the
head-center. At the closed end, the shell is steadied Dy tne
78
SHRAPNEL MANUFACTURE
tail-center. The bottom of the shell rests against the end
of the arbor which acts as a gage. In this setting, the
external diameter of the forging is rough-turned by four
tools F, mounted on the carriage G. This carriage has a
travel slightly less than two inches, and an automatic throw-
off is provided at the end of the cut that disengages the
tools, draws them back and returns the carriage. At the
rear of the carriage on this machine a facing arm is
mounted on a heavy bar. Turning tools are carried on
this facing arm, as shown, and when the front carriage
Fig. 3. Section through Reed-Prentice Automatic Lathe, showing
Tool Arrangement
feeds longitudinally a cam bracket O, bolted to the carriage,
is carried along with it. Clamped on this bracket is an
adjustable cam N held in place by screws. Cam roll M on
the facing arm contacts with cam N, causing the facing
arm to rock forward as the carriage travels longitudinally.
Referring to the plan view in Fig. 2, tool H, held in the
arm, faces the end of the forging, tool I chamfers the cor-
ner, and tool / cuts the depression for the wave ribs, leav-
ing a projection in the center from which the ribs are
formed. It should be understood that the tools on the
SHRAPNEL MANUFACTURE
79
carriage and facing arm work together. One man can run
two of these machines without trouble.
Third Series of Machining Operations. The third se-
ries of operations on the shrapnel forging is performed
on a 14-inch Reed heavy lathe with a specially large turret,
as shown in Fig. 4. This lathe is fitted with a 12-inch
three-jaw chuck, bored out to 3^ inches to permit the
forging to extend into it. The forging A is put in the
chuck as shown at B, and the jaws grip at C. The first
operation is performed with a bar D carrying a blade cutter
E that rough-bores the powder pocket, and tool F that
Machinery
Fig. 4. Tooling Equipment for performing Third Series of
Operations on 14-inch Extra-heavy Turret Lathe
rough-bores the mouth. The turret is now indexed, and a
boring-bar carrying a blade G roughs out the diaphragm
seat, while an auxiliary tool H faces the shell to length.
At the next indexing of the turret the boring-bar / that
carries the finishing tool / finishes the diaphragm seat and
powder chamber.
Fourth Operation Under-cutting and "Waving" Band
Groove. For the fourth operation, the forging is held in
a 14-inch Reed engine lathe provided with an automatic
attachment for under-cutting and waving the ribs for the
8 3
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SHRAPNEL MANUFACTURE 81
B. Spring D keeps the roll E on the lower slide of the
tool-holder in contact with the cam slot in cam-plate F that
is fastened to carriage R. When the carriage is traversed
toward the chuck, the irregular surface of cam-plate F
engages the roll and forces the tool-holder forward. Side
motion to produce the wave is then effected by face-cam G,
mounted on the chuck and contacting with the roll H. This
roll is supported on a bracket forming an auxiliary slide
S that carries the waving tool C. A stiff barrel spring
keeps slide S in contact with the cam G. Thus, when the
machine spindle revolves, the auxiliary slide is caused to
oscillate back and forth far enough to give the desired
amount of wave.
The under-cutting in the band groove is accomplished by
tools / and / which are mounted on separate tool-slides K
and L. These slides are fed in at an angle to the axis of
the forging, against the action of coil springs M and N,
by the cam surfaces of plate Q in which rolls and P work.
Plate Q is bolted to carriage R which, in advancing toward
the chuck, forces in the under-cutting tools in the manner
just described. The tail-center of this machine is fitted
with a quick-acting mechanism so that it may be withdrawn
quickly to insert a new piece.
Fifth Series of Operations. Before performing the fifth
series of operations, the forging is heated and closed in on
the nose. It is then handled in the following manner: A
Reed 14-inch heavy lathe, equipped with an extra large
turret mounted on a special wide-bridge carriage carries
tools for boring, reaming, threading and final squaring
of the open end, as shown in Fig. 6. The shell forging
for these operations is held in a three-jaw chuck provided
with special jaws. In the first position the rough-boring
of the nose and the rough-facing of the extreme end is
performed with tools B and C. The turret is then indexed
and tools Z), and E finish-ream the hole in the nose and
face the end. The tap F is next brought into position, cut-
ting the thread in the nose.
The turret is again indexed, bringing a special form bor-
ing tool into position. Here the boring tool G is carried in
82
SHRAPNEL MANUFACTURE
SHRAPNEL MANUFACTURE 83
a bar H held in a holder of the cross-sliding carriage type
that is fastened to two faces of the turret. By means of
cross-screw /, the boring tool H may be drawn in or out at
will. This tool operates as follows: As the turret is ad-
vanced, handle / is operated to let tool G enter the nose of
the shell, and, upon the continued advance of the turret,
arrow head M is forced in between and gripped by the fin-
gers N. The turret is now backed away from the chuck,
and while receding acts upon slide P through the medium
Fig. 7. Reed-Prentice 14-inch Heavy Type Automatic Lathe
used for performing Sixth Series of Operations
of roll L and cam groove R. The plate containing cam
groove R is attached to the arrow head M and consequently
is held stationary while the turret is being withdrawn
from the work. This backward movement of the turret
is continued until the tool G is withdrawn from the work
and slide S comes in contact with check-nuts on rod 0,
withdrawing arrow head M from fingers N and allowing
the turret to be indexed ready for the first operation on
the next forging.
Sixth or Finish-turning Operations. The sixth series of
operations is performed on a Reed-Prentice 14-inch heavy
type automatic lathe, similar to that used for the second
84
SHRAPNEL MANUFACTURE
operation, and the machine is also operated in a manner
similar to that previously described. The operations con-
sist in finish-turning the outside diameter of the shell and
turning the radius on the nose. In addition, the copper
rifling band, put on previous to this operation, is turned
to shape. Referring to Fig. 7, the shrapnel shell A is
held by the tail-center at one end and is supported and
driven from the other end by a plug screwed into it. This
plug is held on the live center and is driven by an equalizing
driver, coming in contact with pins in the special faceplate.
Machinery
Fig. 8. Tools for machining Brass Fuse Socket on 14-inch Heavy
Turning Lathe Eighth Operation
Two slides B and C are carried on the front of the car-
riage. Slide C carries three tools D; two of these start in
from the rifling band and turn in toward the nose, and the
other works up toward the rifling band from the closed
end. Tool E, carried in slide B, turns the curve on the
nose of the shell and is controlled in its action by means
of a slot in cam F in which a roller held to the slide oper-
ates. At the rear of the carriage is carried a facing bar
attachment, as previously described in connection with the
second operation. This attachment carries three tools, as
illustrated, for machining the rifling band to shape, facing
the closed end and chamfering the corner.
SHRAPNEL MANUFACTURE
85
Seventh and Eighth Operations. After the sixth oper-
ation, the fuse tube is threaded into the diaphragm, the
bullets put in, and the hot resin poured in to keep them
from rattling. The brass socket is then screwed into the
nose and the fuse tube soldered to it. The shell is now
ready for the seventh operation which consists in cutting-
off the center projection. This is accomplished in a Reed
14-inch engine lathe, provided with a faceplate chuck for
holding and driving the shell at the open end, and a steady-
rest for supporting it close to the point where the cutting is
being done. The shell is now ready for the eighth opera-
tion, which consists in machining the brass socket to shape
'aohlnery
Fig. 9. Shrapnel Case made from Chrome-nickel Steel having High
Tensile Strength on a Cleveland Automatic Screw Machine
with Special Tool Equipment
in an extra-heavy lathe as shown in Fig. 8. The tools
used for machining are retained in a special holder on the
carriage. Tool A, which is used for facing off the fuse
tube and the brass socket, is inverted, starts at the center
and is fed out toward the circumference. The external
surface of the socket is machined with a circular forming
tool C held on a stud D located in block B. The inward
travel of this tool is limited by stop E coming in contact
with the shell.
Making Shrapnel Shells on the Cleveland Automatic.
An unusual example of automatic machine work is that of
producing the shrapnel shell shown in Fig. 9. This shell
86
SHRAPNEL MANUFACTURE
is made from a bar of 3 1/16-inch chrome-nickel steel stock.
The steel has a tensile strength varying from 125,000 to
135,000 pounds per square inch, and is extremely tough.
Fig. 10. Order of Operations on the Shrapnel Case
The work is accomplished on a 314-inch Cleveland auto-
matic, and the tooling equipment, as shown in Figs. 10, 11,
and 12, is interesting. While the general operation of the
Cleveland automatic is well understood by many mechanics,
SHRAPNEL MANUFACTURE 87
the production of this piece illustrates a number of points in
the operation of this machine which are not so well known.
Therefore, it is advisable to explain in detail just how this
interesting job is handled.
The first operation, as the job was originally laid out,
was to feed the stock out to the stop A, shown in Fig. 11,
which is held on the cross-slide and operated by a lever
on the base of the machine. This method has been im-
proved upon since the photograph shown in Fig. 11 was
taken, and the time reduced from twenty-seven and one-
half minutes to twenty-five minutes (see Fig. 10 for im-
Fig. 11. Cleveland 3V4-inch Automatic Screw Machine set up for
making a Shrapnel Case In Twenty-five Minutes
proved method). The second operation is to rough-drill
the large hole with an inserted bit B, step the hole for the
taper reamer with cutter C and rough-turn the external
diameter with cutter D held in a special turning attach-
ment. This attachment envelops the shanks of all six
tools in the turret in order to obtain support. The cutters
in the attachment shown in Fig. 11 work in advance of the
under-cutting forming tool E shown in Fig. 12, which is
held on the rear cross-slide. The time required for the
completion of the operations outlined is thirteen minutes.
if
a
SHRAPNEL MANUFACTURE 89
In the third operation drill H finishes the powder pocket,
and two cutters / counterbore for the tap time required
three minutes. The fourth operation consists in finishing
the diaphragm seat with the counterbore /, finishing the
front end with inserted cutter K and breaking the corner
to facilitate tapping with inserted cutter L, the time re-
quired being forty-five seconds. In the fifth operation the
thread is cut with a tap M held in the tap-holder N in forty-
five seconds. Then the turret is indexed and for the sixth
operation the hole is taper-reamed with reamer O, provided
with four inserted "Novo" steel blades, in ninety seconds.
The last and seventh operation consists in knurling the
band with a knurl P (see Fig. 12) mounted on the front
cross-slide, and cutting off the shell with a cut-off blade Q
retained in a holder on the rear cross-slide time six min-
utes. The total time required to produce this shrapnel
case by the improved methods illustrated by the diagram
in Fig. 10 is twenty-five minutes.
There are several points of unusual interest in the pro-
duction of this shrapnel case. One is the large amount of
stock to be removed to form the hole ; the second is the long
taper-reaming operation difficult work to accomplish sat-
isfactorily on an automatic screw machine and the third
is the long outside forming operation which must be held
to a limit of 0.0005 inch on the diameter. In order to ac-
complish this last operation successfully, the external diam-
eter of the piece is first turned with a cutter held in a
separate turning attachment, leaving only 0.010 inch on the
diameter to be removed by a wide under-cutting or shaving
tool E held very rigidly on the rear cross-slide. Not only
must the case be exact as regards diameter, but it must
not vary f om one end to the other nor at any point through-
out its length. The large shaving tool held rigidly in the
manner illustrated in Fig. 12 accomplishes this result sat-
isfactorily.
The material from which the case is made is so tough
that some difficulty was met with in selecting a tool steel
that would stand up for a reasonable length of time under
cut. The drills and counterbores are tipped with "Novo"
90
SHRAPNEL MANUFACTURE
cutters and all the forming tools, including the cut-off tool,
are also made from the same steel. The only cutting tool
in the entire tooling equipment not made of this steel is
the tap. The bar is rotated at sixty-four revolutions per
minute, giving a surface speed for the external cutting
tools of approximately fifty-one surface feet per minute.
Machining the British Forged Shell on Potter & John-
ston Automatics. In making the British forged shell on
Fig. 13. First Operation on Shrapnel Shell, performed on a No. 6A
Potter & Johnston Automatic Chucking and Turning Machine
the Potter & Johnston automatic chucking and turning
machine, three operations complete the work. The first
operation completes the outside of the shell, except for the
extreme end which is covered by the gripping mechanism
of the chuck. The second operation finishes the inside of
the shell and at the same time finish-turns the extreme
open end. After the second operation is performed the
shell is "nosed," which consists in heating it in a lead
C 0> <U
C ^ rC
i
C 01
ro c
SHRAPNEL MANUFACTURE 93
nose of the spindle of the machine. The shell is pushed onto
this arbor until the end of the arbor strikes the bottom of
the shell. The gripping mechanism which comprises six
jaws B and a draw-in plunger C is contained inside the
arbor. The external diameter of the arbor is machined to
practically the same shape as the internal diameter of the
shell, but is smaller. The jaws are held in slots which con-
trol their movement in every direction except radially. They
are forced out radially by means of the draw-in bar C which
is provided with tapered seats that engage the inward end
of the jaws. The bar C is operated by a hand lever D that
extends up over the top of the machine, is f ulcrumed in a
bracket on the rear bearing cap, and is connected to a slid-
ing sleeve E.
In clamping the work on the arbor, lever D is lifted up,
this action drawing the sliding collar E to the right along
the sleeve F, which, in turn, allows the forward end of the
fingers G to close in. This releases the pressure of the
outer end of the fingers on the draw-in bar C. When the
pressure from bar C is released by means of handle D,
heavy coil springs H then come into action forcing the
draw-in bar back and expanding the clamping jaws. Ad-
ditional clamping means are provided by three set-screws
which are brought to bear on the work after it has been
clamped in position by the jaws. To release the work, the
reverse action takes place, that is, lever D is forced down
which slides the collar E to the left, operating the fingers G,
which, in turn, overcome the pressure of the springs H t
allowing the clamping jaws B to collapse.
First Machining Operation Set-up. The order of the first
series of operations in machining a forged shrapnel shell
is as follows: First, rough-turn 7 inches along body of
shell, face end and chamfer; second, finish-turn 21/2 inches
along shell ; third, rough-groove for copper band and dove-
tail; fourth, turn waves in groove.
For the first operation, the work is held on the expand-
ing arbor shown in Fig. 14, and the tool equipment, which
is of an unusually interesting character, is shown in Fig.
15. The first rough-turning operation, accomplished by
94
SHRAPNEL MANUFACTURE
turret tool A, which is of the relieving type to be described
later, is held on the first face of the turret and roughs down
the body of the shell. On the opposite side of the holder
is a roller support B which supports the shell while the
turning tool is in operation. The end of the shell is faced
by means of a facing tool C which is really a type of fac-
ing mill. The end of the shell is then chamfered by means
of a chamfering tool D that removes the sharp corner.
After these operations have been performed, the turret
is indexed and the second face of the turret is brought in
Machinery
Fig. 16. Details of Relieving Turning Tool-holder shown in Fig. 15
line with the chuck. This operation is accomplished with
a relieving tool-holder E carrying a cutter e, which takes a
cut 2% inches along the body of the shell. An interesting
feature of this tool is that on the return stroke of the
turret it swivels back out of the way so that the shell is
not scored by the tool dragging over it. The construction
of this tool is more clearly shown in Fig. 16.
As is clearly shown in this illustration, the turret reliev-
ing turning tool comprises a shank on which is fulcrumed
a tool-holding member B. This is slotted out to carry the
turning tool C which is clamped in place by two set-screws
D and is adjusted to turn the correct diameter by means
SHRAPNEL MANUFACTURE 95
of an adjusting stud and clamping nut F and G. The
method of operating this tool is as follows : The f ulcrumed
tool-holder B is "held up" by means of a fillister-head screw,
screwed into a stud H and acted upon by a coil spring /.
A hole to receive the stud is drilled in the tool-holder B,
allowing about 1/16 inch clearance. When the tool is in
action it has a reverse position to that shown in the illus-
tration, that is, the turning tool instead of being parallel
with the center line is at a slight angle with it. In action,
as soon as the turret advances, the tool comes into contact
with the work, and the work, turning around, forces the
cutting tool down and consequently depresses the spring,
at the same time bringing the "lower part" of the hole
into contact with the extended plug on the holder. In this
way the tool is held rigidly and in contact with the work.
As soon as the turret begins to move back, however, and
the cutting pressure is released, the spring comes into
action and throws up the tool, bringing it out of contact
with the work.
Upon the completion of the operation which is accom-
plished from the second turret face, the turret is again in-
dexed and the next operation is performed from the rear
cross-slide and the third turret face. The third operation
consists in cutting the grooves for the rifling band, and,
on account of the under-cutting necessary, involves some
interesting points. In order to hold the work rigidly while
the grooving tools are acting on it, a revolving support F
is brought in from the turret. The wide tool G for cutting
the band grooves (this tool removes the greatest amount
of the stock) is held on the rear cross-slide and is of the
under-cutting type; that is to say, it operates under the
work or tangentially instead of radially. Held on a bracket
on the third turret face are two tools H and 7, the purpose
of which is to dovetail the rifling band grooves. These
turret tools are held in a holder working in a slide on the
bracket fastened to the turret face and are operated by a
block held on the rear cross-slide. The action of these
three tools, therefore, is simultaneous. The wide grooving
tool, however, is slightly ahead of the dovetailing tools.
1 =
s
c c
3 o
^ o
O v
H 6
SHRAPNEL MANUFACTURE 97
The last operation is accomplished when the turret is in-
dexed to the fourth position. Here, again, a roller support
/ steadies the work while the waving tool is in action on it.
The two waves that are formed are for the purpose of pre-
venting the rifling ring from turning, and they deviate
about 1/16 inch laterally from being a true annular rib.
The tool for cutting these ribs is shown at K and is of
the forming type held in a dovetailed groove in the holder L.
This also carries a roll M which contacts with the waved
surface of the face-cam N, the curve of which gives the
correct out-and-in motions to the waving tool K. The cam
face is on a sleeve that is threaded onto the nose of the
spindle of the machine, as is shown to the left of the
illustration opposite the first turret face.
Method of Holding Shell for Second Operation. The
second series of operations on the shell is also performed
on the Potter & Johnston automatic chucking and turning
machine. The shell is held at the base end by a special
collet of the draw-in type, as shown in Fig. 17. Fixed
in the nose of the spindle is a positive stop A against which
the shell is held by means of the draw-in collet B. This
collet extends into the draw-in rod C, to which it is at-
tached. The method of operating this gripping mechanism
differs slightly from that shown in Fig. 14. In this case
the spring collet B is drawn into a tapered sleeve to clamp
it on the work. This is effected by means of lever D which
is fulcrumed in a bracket extending from the rear bearing
cap of the machine and operates a sliding cam sleeve E.
The cam, in turn, operates fingers F, only one of which is
shown, the latter acting upon the draw-in rod C to which
the collet is attached. By depressing lever D, the chuck is
opened by means of the coil springs G which act upon the
draw-in rod C when the pressure of the fingers has been
released. Lifting up handle D closes the chuck, and de-
pressing it opens the chuck.
Second Series of Machining Operations on Shrapnel Shells.
The operations on the shrapnel shell performed in the
second setting are shown in Fig. 18. The relieving tool A,
held on the first face of the turret, covers that section of the
98
SHRAPNEL MANUFACTURE
shell which in the former operation was held in the gripping
jaws. While this cut is being taken, a turret tool B rough-
bores the powder pocket and diaphragm seat. The reliev-
ing tool A is constructed and operated similarly to the
relieving tool described in connection with Fig. 16. It will
be noted here that the threads on the spindle nose are pro-
TAPER TURNINO TOOL CARRIED
ON FRONT CROSS-SLIDE AND
OPERATED BY TURRET.
REVERSE MOVEMENT OF TOOL
OBTAINED BY USING RACK
AND PINION.
Fig. 18. Tooling Equipment used on No. 6A Potter & Johnston Automatic
Chucking and Turning Machine for performing Second Series
of Operations on Forged Shrapnel Shell
tected by a cast-iron cap to prevent them from being in-
jured. Upon the completion of the operation just described,
the turret is indexed, bringing the second face in line with
the spindle. Here the diaphragm seat is finished with a
flat cutter C, which is held in the boring tool illustrated.
The turret is again indexed into the third position, where
the powder pocket is finished by means of the flat cutter D.
SHRAPNEL MANUFACTURE 99
The turret is now indexed to bring the fourth face in
line with the spindle where the extreme open end of the
shell is turned taper by means of a tool E that is carried
on the front cross-slide and operated by the turret. By
referring to this illustration, it will be noticed that the
taper is turned from the spindle toward the outer end
of the shell and is, therefore, a reverse turning operation.
The tool is caused to move toward the turret by using a
rack and pinion to reverse the movement. On this opera-
tion, as well as on the previous one, one man takes care of
four machines.
Fig. 19. Machining Inside of Shrapnel Shell, and threading with
Automatic Collapsible Tap on Potter & Johnston
Automatic Chucking and Turning Machine
Third Machining Operation on Shrapnel Shells. Before
any other machining operations are done on the shell, it
is taken to a lead bath where it is heated and afterward
placed under a press which closes in the nose or open end
of the shell. For machining in the third operation, the
shell is held practically in the same manner as for the sec-
ond operation, except that it is gripped farther along the
body. The machining performed in this operation is as
follows: On the first turret face, rough-bore and finish-
bore for a distance of 1 inch from the end of the shell;
second turret face, rough-bore the inside of the shell for a
distance of 1 inch back from the thread ; third turret face,
100
SHRAPNEL MANUFACTURE
finish-form on the inside for a distance of 1 inch back of
the thread; and fourth turret face, thread with a collapsi-
ble tap. The various machining operations on the 3-inch
size of shrapnel shells are performed on a standard Potter
& Johnston 6A automatic chucking and turning lathe. It
is recommended that these machines be run in batteries or
2o OPERATION
3o OPERATION
Fig. 20.
First Series of Operations on "Frankford" Shell on a Potter &
Johnston 6A Automatic Chucking and Turning Lathe
units of seven each, four machines being set up for the
first operation, two machines for the second operation, and
one machine for the third operation.
Machining "Frankford" Forged Shell. The machining
of the American or "Frankford" 3-inch type of high-explo-
sive shrapnel shell is comparatively easy, inasmuch as there
is no nosing to be done, and the entire shell may be machined
SHRAPNEL MANUFACTURE
101
at two settings. Fig. 20 shows the way in which the first
operation is taken care of on the No. 6A Potter & Johnston
automatic chucking and turning lathe. The forged shell is
held on an expanding arbor of the same type as that shown
in Fig. 15. In the first turret position, the operations con-
4TM OPERATION
3RD OPERATION
1ST OPERATION
2ND OPERATION
Fig. 21.
Second Series of Operations on "Frankford" Shell on Potter &
Johnston Automatic Chucking and Turning Lathe
sist in taking a straight cut across the diameter and facing
off the end. The external turning tool A is of the relieving
type, and B is a facing tool that works on the end. Both
of these tools are supported and operated from the turret.
A roll support, not shown, steadies the work while tool A is
102 SHRAPNEL MANUFACTURE
working. The turret now backs out, and a forming tool,
held on the cross-slide, advances, cuts the rifling band and
the semicircular grooves in the end of the shell, and at the
same time chamfers the corner. Knurl D, held on the rear
of the cross-slide, is then advanced. This knurls the bot-
tom of the rifling band groove.
By referring to Fig. 20, it will be seen that the grooves
do not extend entirely across the face of the knurl, but
instead two "knurl" ribs similar to a double thread are
formed on the periphery. This construction makes it pos-
Fig. 22. Three-inch Shrapnel Shell made on a Gridley
Automatic Turret Lathe
sible to sink the knurl into the work to the proper depth
without exerting excessive pressure on the arbor and throw-
ing it out of line.
Second Series of Operations on "Frankford" Forged
Shrapnel Shell. For the second series of operations, the
"Frankford" shrapnel shell is held in a draw-in collet as
shown in Fig. 21. As the shell has been completely ma-
chined on the outside, it is let into the collet for a consid-
erable distance. For machining, it is shown gripped in
the collet by jaws A and is backed up by positive stop B. At
the first turret face, tool C rough-bores the diaphragm
seat, tool D bores the thread diameter, and tool E faces
and chamfers the end. The turret is now indexed, and
tools F, G, and H perform similar finishing cuts. A holder
held on the third turret face carries tool / that chamfers
the powder pocket, and at the fourth turret face a collapsible
tap threads the open end.
SHRAPNEL MANUFACTURE
103
Making Shrapnel Shells on the Gridley Automatic Turret
Lathe. Figs. 22 to 25 show a three-inch shrapnel shell
made on the 3 14 -inch Gridley single-spindle automatic tur-
ret lathe. The steel from which the shell is made is very
tough. The specifications are from 125,000 to 135,000
pounds tensile strength, 110,000 pounds elastic limit,
Fig. 23. Tool set up for Producing the Shell shown In Fig. 22
a twenty-five per cent reduction of area, and a twelve per
cent elongation. It will be seen from the above specifica-
tions that the steel is, of necessity, very tough and difficult
to work; in addition, a large taper reamer must be used,
and the outside of the shell must be relieved throughout the
central portion. It is also necessary to machine the piece
to extremely accurate dimensions, all of which tends to
make the work still more difficult. Fig. 22 shows a view of
, , v
*e* '
104
SHRAPNEL MANUFACTURE
the shrapnel shell. It is approximately three inches in
diameter and eight inches long, and the limits allowed for
the sizes are extremely close throughout, both inside and
outside. Figs. 24 and 25 show the successive steps em-
ployed in machining the piece complete, the four views
START OF DRILL
Fig. 24. Successive Steps and Operations employed In Making the
Shell shown in Fig. 22
presented representing the appearance of the work and
the operations performed at each indexing of the turret.
Fig. 23 will enable the operation of the different parts to be
more clearly understood.
SHRAPNEL MANUFACTURE
105
While the operation of the Gridley automatic turret lathe
is generally understood by mechanics, it may be well to
state briefly the general principles upon which work is
done in the single-spindle machine. In this type of ma-
chine, the position of the work does not change as it does
CUTTING OFF TOOL- THIS CAN BE
GROUND AND RESET WITHOUT
CHANGING ADJUSTMENT
13 M!N. 45 SEC.
START OF REAMER
KNURLING IS DONE ON HIGH .
BEFORE REAMER OR CUTT;NG OFF
TOOL COMMENCES TO WORK
22 MINI. 35 SEC.
FINISH OF REAMER
22 MIN. 45 SEC.
START OF FINISH REAMER
S REAMER IS WITHDRAWN PART WAY
TO CATCH PIECE WHEN CUT OFF
28 MIN. 15 3EO. FINISH OF REAMER
26 MIN. 35 SEC. STOCK FED AND DRILL
READY TO START ON SECOND PIECE
AVERAGE TIMEI-27 MINUTES
Machinery
Fig, 25. Successive Steps and Operations employed in Making the
Shell shown in Fig. 22
in the multiple-spindle machine, but the turning is accom-
plished by the operation of tools mounted on tool-slides
which, in turn, work on a turret that revolves about a hori-
zontal axis, successively presenting the tools for operation
upon the work. This will be readily understood by glanc-
106
SHRAPNEL MANUFACTURE
ing at the illustration Fig. 23. It will also be noticed from
this illustration that the forming tools and cutting-off tools
are operated from a face-cam at the lower part of the ma-
chine. The forming slide is actuated by a cam-groove cut
in one side of the cam-plate while the cutting-off slide re-
ceives its movement from a cam-groove on the reverse side
of this plate.
At the first position of the turret, a large 2 11/32-inch
high-speed oil drill is run into the bar to a depth of 6 1/32
inches, and, at the same time, a knee-turner located on the
tool-slide turns the outside of the stock, thereby removing
Fig. 26. First Chucking on Warner & Swasey Turret Lathe for
machining British Forged Shrapnel Shells
the scale from the bar. Referring to Fig. 23, which shows
the turret in the third position, the end of this large drill
is shown at A, and, of course, when at work, it would be
in the position of the reamer which is shown at F. The
time elapsed at the completion of this part of the work is
eleven minutes, five seconds.
At the second position of the turret, a smaller drill, 2 1/16
inches in diameter, which is shown at B, is run in at the
bottom of the hole previously drilled to a depth of 29/32
inch. At the same time a counterboring tool, which is lo-
SHRAPNEL MANUFACTURE
107
cated at C and which is attached to the drill with a set-
screw, is at work counterboring the end of the hole in the
shell. During the time that this drilling and counterbor-
ing operation is being performed, the forming tool shown
at D is being fed into the outside of the head of the shell,
finishing the three grooves as shown; in addition, a sizing
tool E, which is at a fixed distance from the forming tool,
comes in and sizes the work to exactly the right length.
The time elapsed up to the finishing of this part of the work
is thirteen minutes, thirty-five seconds.
2ND OPERATION
FACE END, ROUND
CORNER, AND FORM
BAND GROOVE
UNDER-CUT BAND GROOVE
Machinery
Fig. 27. Diagram illustrating Position and Relation of Tools for
First Chucking on British Forged Shell
At the third position of the turret, which, by the way, is
the one shown in Fig. 23, the large taper reamer F is run
in, which operation removes the bulk of the stock for the
taper, and a second step at the end of this reamer finishes
the extreme end of the hole at the bottom of the shell. The
blades of this reamer are nicked to break the chips as they
are being formed. Before the reamer begins to cut, the
knurling tool H is brought against the work (while it is on
108
SHRAPNEL MANUFACTURE
the high speed) by the cutting-off slide, which, of course,
results in a better knurled section than would result if the
knurling of the piece were done at a lower speed. During
the reaming operation, the cutting-off tool G is run in part
way to facilitate the final severing of the piece. In addi-
tion, the relieved part of the work is turned by a tool
mounted in a tool-holder on the slide of the turret. This
tool is shown at / and it is operated by a templet / which
has a raised projection that throws the tool into the work
after it has reached the right position with relation to the
length of the shell. The total time elapsed up to the fin-
Fig. 28. Set-up on Warner & Swasey Turret Lathe for Second
Series of Operations on Forged Shrapnel Shell
ishing of this part of the work is twenty-two minutes, thirty-
five seconds. At the fourth and last position of the turret,
a finishing reamer sizes the outer end of the interior of the
shell and is withdrawn but part way, so that, when the cut-
ting-off slide comes in and finishes severing the piece, the
shell is caught on the reamer and not allowed to drop and
possibly be injured by so doing.
The average total time for making this piece complete is
twenty-seven minutes. On account of the rigidity of the
tool support, the tools do not require sharpening more
often than once for fifty pieces, with the possible exception
SHRAPNEL MANUFACTURE
109
of the cutting-off tool, which must be sharpened after about
half that number of pieces have been completed.
Using Warner & Swasey Turret Lathe for Machining
Forged Shrapnel Shells. In Fig. 26 is shown a typical
set-up on a Warner & Swasey No. 2A universal hollow-
hexagon turret lathe for machining an 18-pound shrapnel
shell forging. The arrangement of the various tools for
performing the first series of operations is more clearly
illustrated in Fig. 27, to which reference should now be
made. The forging is located for machining on a special
SPECIAL GUIDE FOR
STANDARD TAPER
TURNING ATTACHMEN
2ND OPERATION
FINISH
Machinery
Fig. 29. Diagram illustrating Sequence of Operations performed
at Second Chucking
arbor fitted into the spindle and carrying two spring-con-
trolled centering bushings A. These serve to locate the
shell, which is then gripped by the floating jaws of the
chuck on the external diameter, and a stop on the end of
the arbor locates the shell from the bottom of the powder
pocket.
The first operation consists in taking a cut from the ex-
ternal diameter with a special box-turner provided with a
roll steadyrest and carrying two turning tools. The second
operation is handled from the cross-slide, the shell forging
meanwhile being supported by a roll steadyrest clamped to
the turret. In this operation the closed end of the shell is
110 SHRAPNEL MANUFACTURE
faced with tool C, the corner rounded, and the band groove
formed with forming tool D. The third operation first
chucking is performed with tool F which produces the
waves in the band groove, and is operated in the following
manner: Referring to the lower left-hand corner of the
illustration, it will be seen that a roll G is brought in con-
tact with the face-cam B, thus giving the desired oscillating
movement to the waving cutter. The fourth and final oper-
ation consists in under-cutting the band groove with a tool
clamped to the turret. This tool gages from the end of the
shell by a revolving stop H, and is provided with two slides,
Fig. 30. Third Chucking Set-up on British Forged Shrapnel Shell
set at the desired angle to each other and the work, carry-
ing under-cutting tools / and J. These slides are operated
by handle K.
The second chucking on this shell is handled as shown in
Figs. 28 and 29 on the same type of machine. As shown in
Fig. 29, the shell for this operation is gripped in an auto-
matic chuck, and a stop A for locating it is held in the
spindle. The first operation consists in roughing out the
powder pocket and diaphragm seat with a cutter B, and
rough-turning that portion of the shell held in the chuck
SHRAPNEL MANUFACTURE
111
in the previous chucking with a tool C. This tool is held
in the cross-slide toolpost, and is controlled in its movement
by a special guide fastened to the regular taper-turning
attachment. The second operation finishes the powder
pocket and diaphragm seat with a cutter D.
2ND OPERATION
BACK-FACE
3RD OPERATION
THREAD
Machinery
Fig. 31. Diagram illustrating Relation of Tools for performing
Third Series of Operations
ND OPERATION
COUNTERBORE AND TURN
Machinery
Fig. 32. First Chucking on French Shell made from Bar Stock
on Warner & Swasey Turret Lathe
After the second chucking, the shell is heated on the nose,
closed in and is then brought back to the turret lathe, when
the operations are performed as shown in Figs. 30 and 31.
112
SHRAPNEL MANUFACTURE
Here, again, the forging is held in the automatic chuck and
is located by a plug A in the spindle. The first series of
operations consists in boring, facing and chamfering the
nose with a counterbore B, and at the same time turning the
external radius on the nose with a tool C. Tool C is held
in the cross-slide square turret and is controlled in its
movement by a special guide fitting on the regular taper-
turning attachment.
The second operation, shown to the left of the illustra-
tion, consists in machining the radius inside the nose with
1ST OPERATION
TURN
2ND OPERATION
FACE END, CHAMFER
AND FORM
3RD OPERATION
KNURL
TAPER-
ATTACHMENT
ERATION
TAPER
1 | 1
II
LJ
"v^
Machinery
Fig. 33. Second Chucking on French Shrapnel Shell
a tool E, controlled in its movement by the special guide D,
as previously mentioned. The third and final operation
consists in cutting the thread with a collapsible tap F.
Using Warner & Swasey Turret Lathe for Machining
Bar-stock Shrapnel Shells. The method of machining
shrapnel shells from bar stock differs somewhat from that
used for forgings, and is handled on a No. 2A universal
hollow-hexagon turret lathe. In this particular case, the
shell blank, previous to machining in the turret lathe, is
SHRAPNEL MANUFACTURE
113
rough-drilled in a high-powered drilling machine to the bot-
tom of the powder pocket. Assuming that this has been ac-
complished, the operations for the first chucking are then
carried on as illustrated in Fig. 32. Here the shell is held
in an automatic chuck and is located by a stop A. The first
operation consists in counterboring the mouth with the
counterbore B, and rough-turning the external diameter
with tool C; second, counterboring with the cutter D and
turning further along the shell with a tool E; third, finish-
ing the bottom with a cutter F and facing the end of the
shell with a tool G.
3RD OPERATION
ROUGH CHASE
THREAD
1ST OPERATION
RECESS
2ND OPERATI
BORE, FACE, AND
TURN TAPER
f~-
\ r 1
/
o (^
y
1 /-*T~
jt-
4-TH OPERATION
FINISH THREAD
SPECIAL GUIDE FOR
STANDARD TAPER ATTACHMENT
Machinery
Fig. 34. Third and Final Chucking on French Shrapnel Shell
In the second chucking, the operations shown in Fig. 33
are performed. Here the shell is reversed in the automatic
chuck and is located, as before, by a stop A. The first
operation consists in turning that portion of the body held
in the chuck in the previous chucking with a roll-supporting
turning tool B. Second, supporting the shell with a roller
support C held on the turret, facing the end with a tool D,
and chamfering the band groove and the end with a cutter E
held on the cross-slide square turret. The third operation
is to support the shell from the turret, knurling with a
114
SHRAPNEL MANUFACTURE
knurl F from the cross-slide square turret. Fourth, taper-
turn from the end to the band groove with a tool G, guided
by the taper-turning attachment.
For the third chucking, the shell, as indicated in Fig. 34,
is held in the same manner as for the first chucking. First,
it is recessed with a tool A and brought into action by oper-
ating the special holder which has a cross-sliding movement ;
second, it is bored and faced with a counterbore B from the
turret, and taper-turned with a tool C operated by a special
guide from the taper-turning attachment. In the third
operation, the thread in the nose is rough-chased with a
--WT-
Machinery
Fig. 35. Diagram showing Method of holding and performing First
Series of Operations on Forged Shells on "Lo-swing" Lathe
tool D, controlled in its movement by the chasing attach-
ment of the machine; fourth, the thread is finished with a
tap and tap-holder E.
Machining Shrapnel Shell Forgings on the "Lo-swing"
Lathe. By adding a simple carriage to its "Lo-swing"
lathe, the Fitchburg Machine Works, Fitchburg, Mass., has
adapted this machine for machining shrapnel shells of dif-
ferent types.. The following data and illustrations refer
particularly to tooling used for machining the Russian and
French shells. On the Russian shell, after centering, the
SHRAPNEL MANUFACTURE
115
forging A is held on a special arbor B shown in Figs. 35
and 36. Placed over this arbor is an expanding collar C,
the inside surface of which is chamfered to fit against sur-
face D on the stem of the arbor. The section of the arbor
next to the spindle is threaded and a large nut and hand-
wheel E are turned to pull the sliding sleeve C along the
arbor and thus expand it to firmly grip the inside of the
shell forging. Sleeve C is connected to the nut E by a
threaded collar F. After the forging is securely located on
the arbor, which it should be understood extends to the
bottom of the powder pocket to gage it for length, the tail-
center G is run in to support it.
Fig. 36. Set-up for performing First Series of Operations on
Russian Forged Shell on "Lo-swing" Lathe
To those familiar with the "Lo-swing" lathe, it will be ap-
preciated that its chief efficiency lies in its system of multi-
ple turning tools. Thus, on this job, tools H, I, J, K, L, and
M are all mounted on one slide, and in the illustration are
shown in the positions they occupy after taking their re-
spective cuts. At the beginning of the cut, turning tools K,
L, and M are drawn back clear of the work to allow suf-
ficient clearance for tools H and I to operate. With the
tools drawn back and the carriage at the extreme right of
the bed, tool H is the first to come in contact with the work.
This tool takes a roughing cut over the body of the forg-
ing, finishing at the radius on the nose.
116
SHRAPNEL MANUFACTURE
Tool H is controlled in its action by a former pin on the
tool-slide, held in contact with the face of cam former by
a stiff spring. Former slide O takes the place of the regu-
lar taper-turning former ordinarily used on the "Lo-swing"
lathe. When the former pin in the slide carrying tool H
reaches point P on former O, the tool is withdrawn to con-
form with the shape shown at N on the forging. The tool
is then fed in further toward the axis of the arbor, until
the former pin reaches point Q on the slide, when the radius
on the nose is completed. Tool H is the only one mounted
on a taper-turning block.
Machinery
Fig. 37. Diagram showing Method of performing Second Series of
Operations on Forged Shrapnel Shells on "Lo-swing" Lathe
Just after tool H passes point N, tool I commences to cut
at the end of the forging, taking a finishing cut and ending
up in the position in which it is shown in the illustration.
After tool / reaches this position, the other tools J, K, L, and
M are brought into action. Tools K, L, and M are so sit-
uated on the carriage that no lateral feeding is required.
When these tools are in action, the roller support R takes
the thrust. Tool K roughs out the band groove and is fed
into the work by a handwheel. Tool L cuts the groove for
attaching the brass case to the shell, and tool M, carried on
the same block, faces the end. Tools K, L, M, and S are
located on the same carriage and are fed in together. Tool
SHRAPNEL MANUFACTURE 117
S rounds the corner of the shell. The carriage on which
tools K, L, M, and S are located is now drawn back out of
the way, and the entire carriage moved over so that tool J
can be used to under-cut the rifling band groove. After
cutting off the center projection, the first series of opera-
tions on the shell is completed.
Second Series of Operations on the Russian Shell.
The second series of operations is performed on the inside
of the shell on the "Lo-swing" lathe, which is provided with
a special turret for this purpose. As is shown in Figs. 37
and 38, the shell A is held in special collet jaws B that have
a two-point bearing on the shell. Stop C in the spindle
Fig. 38. Set-up on "Lo-swing" Lathe for performing Second
Series of Operations on Russian Shell
locates the shell in the chuck. To manipulate the chuck for
tightening it on the work, handwheel D is turned, carrying
with it the nut E and ring F. Ring F carries pins sliding
in slots in sleeve H and driven into collet B, so that when
nut E is drawn back it also carries collet B into the taper
in sleeve H, closing the collet on the work. Turning hand-
wheel D in the opposite direction releases the grip of the
collet B on the work. The first operation is performed
with tools /, /, K, and L. Tool / bores the powder pocket,
tool / roughs the diaphragm seat, tool K rough-turns the
thread diameter at the shell mouth, and tool L faces the
end. The turret is now indexed, and boring-bar carrying
118
SHRAPNEL MANUFACTURE
tool M is brought into operation. This tool turns the curved
interior of the shell. To accomplish this, the turret lock-
ing-pin is removed, allowing the turret to float on its cen-
tral axis. Fastened on the ways of the lathe at the rear
of the turret by a clamp O is the cam bracket N carrying
the guiding cam P. This cam, through pins Q and R in
bracket S, controls the float of the turret and guides the
cutting tool M. In the illustration, the tool is shown at the
Machinery
Fig. 39. Diagram showing Method of machining French Shells on
"Lo-swing" Lathe First Series of Operations
end of the cut. It will also be noted that one surface of
the cam is curved and the other is straight; therefore, to
compensate for this and also to steady the turret, pin R
is backed up by a spring. Clamp O is now released and
bracket N moved back to allow the turret to be indexed.
Bracket N is located, when brought into the operating po-
sition, by a stop on the bed of the lathe.
.
T,
s
.E B,
&
o &
3 :
J2? "E
. -s|
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05
JSis
r- <D ;
T3 ^
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C3 CO JO JH
i i C3 ^ p> t
"^3 QJ rti o.
<m
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C^ S
3 5* o
M 8 3 .8 ft
O
119
120 SHRAPNEL MANUFACTURE
great many of the French shells are made from solid bar
stock, and when this is the case, the first operation, per-
formed as shown in Fig. 39, consists in rough-drilling. If
the shell is made from a forging, this operation, of course,
is dispensed with and the first tool used carries boring and
facing cutters, as shown at A, B, C, and D. These rough-
bore the three diameters on the inside of the shell and face
off the end to length. The next operation is accomplished
with two finishing boring tools E and F, the depth of which
is obtained by an adjustable collar G that comes against the
Fig. 41. Set-up on "Lo-swing" Lathe for performing Second
Series of Operations on Straight Type of French Shell
produced with a collapsible tap H. The turret is then in-
dexed two holes, bringing the special recessing tool into
position. This tool is of the cross-slide type and carries a
back recessing cutter /. This completes the first series of
operations on the shell.
Second Series of Operations on Shell. French The sec-
ond series of operations on a French shell is accomplished
as shown in Fig. 40. Here the shell is held in the same
manner as described in connection with Fig. 35. The forg-
ing is placed on arbor B that has an expanding sleeve C
operated by the hand-clamping wheel nut D. Eight cutting
1ST CHUCKING
2ND OPERATION
1st CHUCKING
3RD OPERATION
Fig. 42. Set-up and Tool Equipment on the "Llbby" Turret Lathe
121
122 SHRAPNEL MANUFACTURE
tools are located on the carriage. Tool A turns the diame-
ter at the open end of the shell, B the central part, C cuts
the band groove, D chamfers the section adjacent to the
band groove, E chamfers the end of the shell, and F knurls
the band groove. Roll G, in connection with roll H, sup-
ports the shell while the knurling is being done, whereas
tool / faces off the end of the shell. At the beginning of
the cuts, tools C, D, E, and knurl F, also roll G and tool /,
are withdrawn. This permits tool A to cut the front end
of the shell at the beginning and finish the diameter at the
open end of the shell. Tool B next comes into action and
turns the central part of the shell. Tool C is then located
in the correct position for the band groove and the carriage
on which tools C, D, and E are located is fed straight in,
cutting the band groove -and chamfering. Knurl F is then
brought into position to knurl the groove, with roll G
backing up the work against roll H. The last operation
is to cut off the center projection with tool /.
Fig. 41 shows the tool set-up on the "Lo-swing" lathe for
machining the straight type of French shell, in which two
tool-blocks are used for doing the straight turning. The
leading tool turns the end of the shell a little larger than
the main body. The procedure for grooving, knurling, and
facing the shell is that previously described for the forged
shell, which is shown in Fig. 35. On the French shrapnel
shell the second operation follows directly after the first,
whereas on the Russian forged shell a nosing-in operation
comes between the two machining operations.
Using the "Libby" Turret Lathe for Machining Shrapnel
Shells. One of the many ways of machining a shrapnel
shell is illustrated in Figs. 42 and 43. This shows the set-up
on the "Libby" turret lathe, manufactured by the Interna-
tional Machine Tool Co., Indianapolis, Ind, In the first
chucking, the forging, as shown at A, is held on a special
solid arbor provided with a series of corrugations where it
contacts with the forging. This, in addition to providing
a rigid support, assists in gripping, and the shell is also
gripped by a pair of chuck jaws that act as drivers. First,
a gang tool-holder carrying three stellite turning tools o is
2ND CHUCKING
2ND OPERATION
SRD CHUCKING
4TH OPERATION
AlacJiincrji
Fig. 43. Set-up and Tool Equipment on the
"Libby" Turret Lathe
123
124
SHRAPNEL MANUFACTURE
1ST CHUCKING-2D OPERATION
D
1ST CHUCKING-
irhi i Tw^ 1
rt-HJ jr\r i j, j ! TK
Ital T-J $iJ
^ 84.
1ST CHUCKING 4TH OPERATION
Fig. 44. Machining Shrapnel Shell Forgings on a 22-inch
Extra-heavy Turret Lathe
SHRAPNEL MANUFACTURE 125
brought into position, and the cutting is started, continu-
ing for a distance of one-third of the length turned. To
provide additional support, a roller back-rest, carrying a
facing tool, is brought in to steady the work, and, as it is
fed forward, the end of the forging is faced off and
chamfered.
The second operation on the first chucking is shown at B.
Here the cutter a is brought in first and starts the band
groove, after which the under-cutting tool b is brought in
to under-cut the edges of the groove. In the meantime,
roller c supports the work. Upon the completion of the
groove, the holder carrying cutter d is advanced to finish-
face the end of the work and chamfer.
The third operation cutting the waves in the band
groove is of an interesting character and is accomplished
as shown at C. A cam e which is free to rotate with the
work is first brought in contact with it ; then the cross-slide
is advanced, carrying the waving tool / and the guide g.
The guide g fits in the cam groove and controls the opera-
tion of the waving tool.
In the second chucking on the first operation the shell is
reversed in the chuck and is held in the manner indicated at
D, Fig. 43. The forging is located in the chuck by a stop-
collar h, and is gripped on the external diameter by the
jaws of the chuck. A stepped boring tool carrying five
inserted blades is brought in to rough-bore the internal
diameters and machine the shell to the proper thickness at
the bottom of the powder pocket. This tool also carries a
facing cutter that faces off the shell to the proper length.
While the boring tool is working, a broad turning tool, held
on the cross-slide, is brought in to bevel the nose prepara-
tory to closing in. The next step is to taper-ream the inter-
nal diameter, as shown at E. This completes the opera-
tions for the second chucking.
The nose of the shell is now heated and closed in, after
which the third series of operations is performed. The
first step in the third chucking is to bore for the thread
and face the end of the shell with a turret tool, as shown
at F. The next operation is to machine the curved con-
126
SHRAPNEL MANUFACTURE
3b
-
3D CHUCKING-FORMING END
J
Machinery
Fig. 45. Machining Shrapnel Shell Forgings on a 22-inch
Extra-heavy Turret Lathe
SHRAPNEL MANUFACTURE
127
tour of the nose of the shell with a special turret tool as
shown at G. Here a wide forming cutter i, held in a turret
tool-holder, is brought in contact with the work, finishing
the nose of the shell to the proper form. During this
operation, the shell is supported by a roller in the holder.
The next operation is to form the inside of the nose of
the shell to the proper shape, as shown at H. This is ac-
complished with a forming blade /, held in a holder clamped
in the toolpost. Following this, a collapsible tap is brought
in from the turret to thread the nose of the shell, as shown
at /.
Machinery
hig. 46.
Method of holding Shrapnel Shells for First Operation
on a 22-inch Turret Lathe
Machining Shrapnel Shells on a Heavy 22-inch Turret
Lathe. Still another method of machining shrapnel shells
in a heavy turret lathe is shown in Figs. 44 and 45. The
shell being machined is an 18-pound British shrapnel shell
made from a forging. It is held on an expanding arbor
for the first operation, as shown in Fig. 46. The arbor is
of the three-point support type and is positive in its grip.
Around the periphery of the nose-piece are located three
pinions A capable of being rotated by a square-ended
wrench. These mesh with teeth in bevel gear B which, in
turn, is threaded onto arbor C. The forward end of this
arbor is cone-shaped and operates the three gripping fingers
in the open end of the shell, whereas another rod passing
through arbor C and connected to plunger D operates,
through the coil spring, the three fingers used in gripping
128
SHRAPNEL MANUFACTURE
the shell by the powder pocket. This arbor holds the shell
securely while the machining operations are being accom-
plished.
The first operation performed at the first chucking of the
work is shown at C in Fig. 44. Here a turning tool-holder
clamped to the turret and carrying two cutters is advanced
and takes a roughing cut from the exterior diameter of
the shell for practically its entire length. The shell is
supported by three roller supports as illustrated. The sec-
ond operation at the first chucking is performed from the
cross-slide, as shown at D. Here a forming tool of the
tangent type roughs out the rifling band groove, leaving
Machinery
Fig. 47. Cutting Square Thread in Nose of French Shrapnel
Shell in "Automatic" Threading Lathe
sufficient metal in the center for the production of the wave
ribs. The third operation is facing off the closed end of the
shell from the turret as shown at E, and the fourth opera-
tion consists in machining the waved ribs as shown at F.
The tool for accomplishing this operation is held on the
cross-slide and is operated from a face-cam on the nose of
the spindle.
In the second chucking the shell is held in a three- jaw
scroll chuck. The first operation is to rough-bore the in-
side of the shell and powder pocket with a tool G, Fig. 45,
held in the turret ; directly after this a finishing tool of the
SHRAPNEL MANUFACTURE
129
same shape is brought in, finishing the surfaces previously
roughed out. The second operation is to face off the open
end of the shell and taper-form back of the nose from the
cross-slide, as shown at H, and at the same time turn that
portion of the exterior surface of the shell not machined
in the previous operation with a tool clamped to the turret
as shown at /.
Previous to the third chucking, the nose of the shell is
heated and closed in. The shell is then held in a three-jaw
Machinery
Fig. 48. Threading Base End of Bar-stock Shrapnel Shells in
"Automatic" Threading Lathe
scroll chuck provided with special jaws. The first opera-
tion, as shown at /, consists in boring and turning the nose
of the shell with a tool held in the turret. Following this,
the hole is reamed with a standard reamer and tapped with
a collapsible tap. Both of these tools are held in the turret,
but are not shown in the illustration. This completes the
machining operations on the shell.
Threading Shrapnel Shells on "Automatic" Threading
Lathes. Considerable difficulty has been experienced in
cutting the square thread in the nose of the French shrapnel
130
SHRAPNEL MANUFACTURE
shell. One method which accomplishes this operation sat-
isfactorily is shown in Fig. 47, and is accomplished on a
12-inch "Automatic" threading lathe built by the Automatic
Machine Co., Bridgeport, Conn., and equipped with special
tools for this purpose. Referring to this illustration, it
will be seen that two tools are used a roughing tool A,
and a finishing tool B. Tool A roughs out the thread to a
shape similar to the Acme type of thread, whereas tool B
squares it up. The roughing and finishing tools are held
on the forward and rear carriages, respectively, and are
Fig. 49. Turning, facing, and threading Plugs for Closed End of Bar-
stock Shrapnel Shells in "Automatic" Threading Lathe
operated simultaneously, being advanced throughout the
length of the thread, withdrawn and returned to start a
new cut. The method of operating the tools is one of the
chief features of the "Automatic" threading lathe.
The base end of shrapnel shells when made from bar
stock is as a rule bored out and a plug inserted to eliminate
any piping effect in the bar. Fig. 48 shows the method of
accomplishing this operation on a 12-inch "Automatic"
threading lathe. The work is held in a three- jaw universal
chuck and is supported by a roll steadyrest comprising two
SHRAPNEL MANUFACTURE
131
rolls that are located beneath the work. On the extended
end of the rear roller stud is fastened a swinging stop that
is used for locating the base of the shell in the correct
position ready for threading. The base of the shell is coun-
terbored in another machine, previous to the threading op-
eration. The threading is done with a circular tool held
on a special internal threading tool-holder, the latter being
retained in the toolpost carriage. The threading tool-holder
can be moved longitudinally to bring it into the proper
relation to the work. It is also held so that the cutting
edge is turned upside down as this action forces the work
Fig. 50. Grinding Shrapnel Shells on a Norton Special-purpose Grinding
Machine
down in contact with the roller supports. By handling
the work in this manner, a steadyrest of the ordinary type
is dispensed with and the operation of the attachment
facilitated.
One method of making plugs for the base end of shrapnel
shells when made from bar stock is shown in Fig. 49. For
this work, a 12 by 4 "Automatic" threading lathe equipped
with special tools designed for this purpose is used. The
machine is provided with a draw-in collet chuck that holds
the rough forged blank. The order of handling the opera-
132
SHRAPNEL MANUFACTURE
tions on this machine is to use the rear tool A for turning
the external diameter of the plug. This is handled at the
same rate of feed as that required for threading, so that it
is sometimes necessary to take more than one cut, depend-
ing on the amount of material left on the diameter. The
vertical slide B is for facing only and carries a cutting tool
C. This is supposed to finish the face in one cut, but as
the work will spring considerably, a light finishing cut is
taken when the tool is being drawn back from the center to
the circumference of the work. The threading tool D is
held on the front toolpost and is of single-point construc-
tion. The feed given to this tool is automatically controlled,
both as to pitch and depth of cut at each traverse.
In actual operation, both the threading and turning tools
are in motion all the time on the work, but the tools are in-
0>
n
.
"\
6
A
4
6
B
C
i- :
?t<-2^
40 42 45
0. Oi
D
1
D
1
LJ XacMncry
Fig. 51. Diagram showing Sclerpscope Hardness Test of Heat-
treated Shrapnel Shell at Various Points along its Surface
dependency controlled so that either one can be operated
separately. A stop is provided on the back toolpost so as
to turn each plug to the same diameter. The automatic
throw-out for the feed of the threading tool is set from the
front handle on the ratchet and pawl as regularly furnished
on the "Automatic" threading lathes.
Grinding Shrapnel Shells. An increasingly large num-
ber of shrapnel shell manufacturers are finishing the steel
shell by grinding instead of finish-turning. That is, the
exterior surface of the shell is rough-turned to within from
0.030 to 0.080 inch of the finished size and is then finished
to the required limits and shape by grinding, as shown in
Fig. 50. It is claimed by the advocates of grinding that
the finishing operations are more speedily performed in this
manner and that a more accurate and concentric shell is
SHRAPNEL MANUFACTURE
133
produced. They also point out the fact that portions of the
shell are so hard that it is extremely difficult, if not impos-
sible, to turn it in the allowable time.
The varied heat-treatment given to the shell on the closed
end and nose leaves it harder in some sections than others,
as indicated in Fig. 51. The section E, 2y% inches from the
closed end of the shell, must strike from 42 to 50 on the
scleroscope, and the section A at the nose must strike be-
tween 20 and 25. The section marked Z), or that part of it
to the left of the line that marks the limit of the heat-
treating on the closed end, has not been heat-treated at all,
k~#~-H
!=[$
DRIVING PIN'
DRIVING PIN _f
r
HEADSTOCK
CENTER
u
B
c
Machinery
Fig. 52. Two-operation Method of grinding Shrapnel Shells on
Norton Grinding Machines
and partly on this account, and also because of the grad-
ually diminishing thickness of the shell along this section,
it strikes between 40 and 45, decreasing as the thickness of
the wall diminishes, until at C the section strikes but 35.
Section B, adjacent to the annealed nose of the shell, strikes
about 30 on the scleroscope.
On the other hand, some manufacturers are not putting
the shell through this heat-treating and tempering process,
and omit the annealing and machining of the nose after the
nosing-in operation. This leaves the nose with considera-
ble stock to remove and in such a condition as regards hard-
134
SHRAPNEL MANUFACTURE
ness that the grinding machine becomes a necessity. In
the face of these varying degrees of hardness of the shrap-
nel shell, it will be seen that it is difficult to secure wheels
of the right grain and grade to suit all of these conditions.
With this information in mind, we can more intelligently
take up the actual grinding of the shell. The Norton Grind-
ing Co., Worcester, Mass., has been actively engaged in
developing methods of grinding shrapnel shells and the fol-
lowing illustrations and descriptions apply to this work.
STOCK jTl __
HEADSTOCK
CENTER
DRIVING Pl?f ;.. J_J~"
HEADSTOCK
CENTER
'"T
< 2V 4
^-WHEEL
|pil
Br-=rt
DRIVING PIN J-i-
HEADSTOCK
CENTER
Machinery
Fig. 53. Three-operation Method of grinding Shrapnel Shells on
Norton Grinding Machines
Fig. 52 shows the two-operation method of grinding the
shrapnel shell. Section A at the open end of the shell is
covered by a wide-faced wheel formed to shape, that fin-
ishes the radius on the nose at one in-feeding of the wheel.
Sections B, C, and D are covered by a wide-faced wheel,
formed to shape so as to finish these three surfaces at one
in-feeding of the wheel. Section E at the closed end of the
shell is finished completely by turning.
SHRAPNEL MANUFACTURE 135
Some manufacturers use a three-operation method of
grinding the shrapnel shell as illustrated in Fig. 53. In
this case, the sections A and D are first ground with the
same wheel, as American manufacturers deem it advisable
to grind surface A rather than to finish it by turning. The
second stage in this grinding is the finishing of the nose E
with a formed wheel, and the third stage is the finish-grind-
ing of the body at points B and C.
Two-operation Method of Grinding Shrapnel Shells.
The procedure followed in grinding shrapnel shells by the
two-operation method is first to screw plugs into the open
Fig. 54. Radius Wheel-truing Device for forming Grinding
Wheel for grinding Shrapnel Shell Nose
end of the shells, as shown in Fig. 52. The outer ends of
these plugs are centered, and the projection left on the
closed end of the shell with the center intact acts as a means
of supporting the shell. Some of the Canadian manufac-
turers vary this practice by cutting off the center projec-
tion on the closed end of the shell and fitting a cap with a
center hole over the closed end. Others use a ball-bearing
cup center to carry the closed end. American manufac-
turers, however, leave the center projection on the shell
until after the grinding has been finished.
In grinding the nose end of the shell, the amount of metal
removed varies from 0.020 to 0.090 inch on the diameter.
136 SHRAPNEL MANUFACTURE
The grinding wheel operates at from 6000 to 6250 surface
feet per minute. The speed of the work is 75 revolutions
per minute, or a surface speed of practically 75 feet, and
the machine used is a Norton 6 by 32 plain grinder. The
wheel used is generally 14 inches in diameter by 214-inch
face. The wheel requires truing for every five to twenty
shells, depending upon the amount of metal removed and
the hardness of the shell. For truing, a simple radius fix-
ture carrying a diamond is used. Fig. 54 shows this wheel-
truing device clamped on the grinding machine bed. It is
applied in the same manner as the usual steadyrests used
Fig. 55. Norton Special Form Wheel-truing Device for truing
Wheel for grinding Shrapnel Shell Body
for supporting the work. The diamond is mounted in a
swinging arm that is operated by a hand lever as shown.
By successive cuts across the wheel, the desired shape is
attained.
For grinding the body either a 10 by 24 special-purpose
or 10 by 36 Norton grinding machine is employed. The
amount of metal removed from the body varies from 0.030
to 0.075 inch on the diameter, and the limits vary from 0.002
to 0.010 inch, depending largely on the requirements of the
plant in which the work is being done. The wheel used on
the body is 20 inches in diameter and is of the ring-wheel
SHRAPNEL MANUFACTURE
137
Fig. 56. Besly No. 14 Ring Wheel Grinder equipped for grinding
Shrapnel, but shown without Hoods and Water Attachments
type. It will be noticed in Fig. 52 that the wheel for grind-
ing the body is also formed to shape. The method of truing
the wheel for shaping the shrapnel shell body is shown in
Machinery
Fig. 57.
Fixture used on Besly No. 14 Ring Wheel Grinder for
grinding Center End from Shrapnel Forgings
Fig. 55. This attachment is clamped to the front of the
grinding machine bed and at the top of the bracket is fitted
a slide A operated by handwheel B. Upon the face of this
138 SHRAPNEL MANUFACTURE
slide nearest the grinding wheel is pivoted an angular arm
C that supports the diamond D at its lower end. Under the
end of the upper arm is a spiral spring that keeps the
diamond normally back from the wheel. A plate former E
clamped to the bottom face of the bracket is shaped to agree
with the form to be given the wheel. At the lower ex-
tremity of the arm and behind the diamond is mounted a
roll F that bears constantly against form E. When the
diamond slide is reciprocated by turning the handwheel, the
diamond is made to traverse a path conforming with the
cam that guides it. By moving the wheel in toward the
diamond and making successive traversings of the diamond,
the wheel is given the desired shape.
Fig. 58. Tools for making Base of Powder Cup
For grinding the body, the wheel must be trued after
every ten to twenty-five shells are ground, depending upon
the amount of metal removed and the hardness of the shell.
In grinding shrapnel shells, the usual method is to fit a lot of
the shells with the driving plugs and carry them all through
to completion before removing the plugs.
Removing Center End From Shrapnel Forgings. For
performing practically all the machining operations on the
shell, a center projection is left on the closed end of the
shell for supporting it. This, of course, must be removed
before the shell is completed. One method of doing this is
to use a Besly No. 14 ring-wheel grinder equipped with a
SHRAPNEL MANUFACTURE
139
special fixture. A Besly grinder fitted up for this work is
shown in Fig. 56, and the fixture used for holding the shell
is shown in Fig. 57. The machine, as furnished, is arranged
for wet grinding, but is not so fitted up in the illustration.
The fixture is fastened to the geared lever feed table and is
of simple design. It is provided with a backing-up stop A,
the work resting in two semi-spherical groove projections
on the fixture. The operator simply holds the shrapnel shell
in place by hand and then feeds it in against the wheel and
traverses it past in the usual manner. The time for remov-
ing a %-inch diameter stub end projecting % inch from the
body of the shell is less than a minute.
Press Tools for Making Powder Cup. In the British
shrapnel shell, the powder in the base of the shell used for
Fig. 59. Tools for making Top Member of Powder Cup
exploding it and ejecting the lead bullets, etc., is held in a
tin-plate powder cup. This is completed in the punch press
in the manner shown in Figs. 58 and 59, and comprises two
parts, a base and a top. The base is made from tin plate
0.022 inch thick, whereas the top is made from 0.036 inch
thick tin plate. The bottom of the cup is completed in one
operation with the punch and die shown in Fig. 58, which is
held in a single-action press. It is turned out from a blank
3 7/32 inches in diameter and is cut out and formed in one
operation. The completed size is 2*4 inches diameter by %
inch high. After cupping, the top edge is trimmed in a
turret lathe. The press operations on the top, as shown in
Fig. 59, are a little more complex. The first operation con-
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140
SHRAPNEL MANUFACTURE 141
ferent governments varies. There are 252 in the Ameri-
can 15-pound shell, and 235 or 236 in the British 15-pound
shell. The bullets used by the U. S. government have six
flattened sides, to facilitate packing, whereas those used
by foreign governments are spherical.
There are several methods of making shrapnel bullets.
One is to cast the bullets in iron molds, which are split in
the center, so that the bullet can be removed when cast.
Another is to cut off slugs from lead wire and strike these
between dies in a heading machine. The bullet heading
machine takes the wire from a reel, cuts it oif , forms it and
trims off the resultant flash automatically. In making the
American bullets, a second operation follows, consisting in
flattening the sides. The Waterbury Farrel Foundry &
Machine Co. furnishes unit equipments for doing this work.
For the flattened bullets, the unit consists of one hydraulic
wire extruding press and fourteen heading machines cap-
able of giving a production of 850. bullets per minute. For
the spherical bullet, the unit equipment consists of one
hydraulic extruding press and eight heading machines, giv-
ing a production of 950 bullets per minute.
The method of casting lead bullets in ordinary molds is
antiquated, and another method somewhat similar to that
just described has taken its place. The first step is to pro-
duce the wire from which the bullets are eventually made.
This is accomplished in two ways. The first is the hot metal
process and consists in pouring the molten lead into a
cylinder, from which it is extruded through a die by a
plunger advanced into the cylinder. By this method, it is
necessary to allow the metal to settle before the press can
operate. An improvement over this is utilized in presses
built by a hydraulic lead press manufacturer of Brooklyn,
and consists in first casting ingots of the required diameter
and length and then charging the press with these instead
of pouring the molten lead into the press chamber. Two
presses have been designed for this process. One has a
capacity of 700 tons and is charged with ingots weighing
150 pounds, whereas the other has a 900-ton capacity and
is charged with 200-pound ingots. The product from these
142 SHRAPNEL MANUFACTURE
two machines is 1800 pounds of lead wire from the small
and 2500 pounds from the large press per hour. The wire
as it is extruded from the die is wound on a reel carrying
2000 pounds of wire.
There are two principal types of swaging machines used
for making these lead bullets from wire. One carries a
single set of dies, whereas the other carries twelve sets of
tools. The operation of the latter will be described. Re-
ferring to the diagram, Fig. 60, twelve reels of lead wire-
not shown are arranged in tandem on stands behind the
press, six reels in a row. The wire is conveyed from these
reels to the dies by a feeding mechanism, being guided to
the individual tools by a plate A, having twelve U-shaped
impressions in its top edge. The wire now passes over a
spring B which serves to lift it up slightly at each stroke
of the press. The tools C and D, as shown, are provided
with half -spherical depressions in their adjacent faces and
are set so that they come within 1/64 inch of meeting. The
dies are guided and controlled in action by a special mechan-
ism, and the press in which they are carried operates at 70
revolutions per minute. This gives a rated production of
840 bullets per minute. As is clearly indicated in the illus-
tration, considerable scrap is formed in making lead bullets
by this process in fact the scrap is about 33 per cent of
the reel of wire; also owing to the setting of the punches
a slight fin is formed around the periphery of the bullet.
After forming, the bullets are taken to a tumbling ma-
chine where they are tumbled for one hour. No other ma-
terial is put into the tumbling barrel, but the action of the
bullets working on themselves satisfactorily removes all the
fins. Both the swaging and tumbling operations must be
carefully watched because of the necessity of having the
bullets a certain weight. The allowable variation on one
pound of bullets is one dram, and there are forty-one bullets
to the pound. Ten pounds of lead rod make 6*/2 pounds
of bullets, and the scrap resulting from the swaging opera-
tion is remelted and used over again. After tumbling, the
bullets are inspected and are then ready for use.
CHAPTER V
MAKING FUSE PARTS
COMBINATION timing and percussion fuses comprise
a large number of small parts made from different metals
and alloys, and are produced in various ways. Some of the
parts are made from brass rod or alloys of copper and
aluminum, whereas others are made from hot-pressed f org-
ings and are machined after being formed to shape. In
the following, a brief description of several different
methods of making the most important fuse parts will be
Fig. 1. Tools used in forging Brass Fuse Socket
illustrated and described, together with details regarding
the forging tools used for the socket and plug.
Forging the Fuse Socket. The fuse socket, which
screws into the nose of the shrapnel shell and acts as a
base for the fuse, is made from a special forgeable alloy
casting containing 40 per cent copper, 58 per cent zinc, and
2 per cent lead. The first step in this process is to melt
the above constituents in the usual manner and then to cast
the slugs in sand molds, six to eight being gated together.
These castings are made 2 11/16 inches in diameter by
11/16 inch thick, as shown in Figs. 1 and 2. There are
several methods in use for forging the plugs, but the gen-
eral principle is the same. In this particular case, a No. 23
143
144
MAKING FUSE PARTS
Bliss press capable of exerting a pressure of 250 tons i&
used. The castings are placed in the furnace where they
are allowed to "soak" at a temperature varying from 1200
to 1300 degrees F., or, in other words, until they reach a
dull red color. One casting at a time is then quickly re-
moved and placed in the impression of the die shown to-
the right in Fig. 1 and in detail in Fig. 2. The working
Machinery
Fig. 2. Diagram showing Construction of Tools used in
forging Fuse Socket
parts of these dies are made from Jessop's high-carbon
tool steel and one blow of the press completes the forging,
turning out about 3000 in ten hours. The tools used for
this purpose are of interesting construction, as shown in
Fig. 2. They comprise a lower die A machined out to the
shape of the finished forging and carrying an ejector, and
MAKING FUSE PARTS 145
lower former B operated by plunger C which ejects the forg-
ing if it sticks in the die. The top member or punch com-
prises a holder D into which the punch E is screwed. This
is bored out to fit an ejector F which ejects the forging as
the ram of the press ascends. Punch E and stripper or
ejector F are made from high-speed steel, hardened. G
shows the cast blank and H the completed forging.
Forging Brass Plugs. The brass plug shown in Fig. 3
is used as a temporary cap for the shrapnel to protect it
during transportation. It remains in the fuse socket until
the shrapnel shell reaches the field of operations, when it
is removed and replaced by the timing fuse. This member
is made from a special forgeable alloy casting 2 inches in
Fig. 3. Tools used for forging Brass Plug
diameter by % inch thick and is cast in sand molds in a
similar manner to the fuse socket. It is also composed of
the same constituents as the socket and is forged in the
same type of press. The construction of the tools,
however, varies somewhat from that of the tools used in
making the socket, as will be seen upon reference to Figs.
3 and 4. The tools for the plug comprise a lower die A
carrying a combined ejector and forming die B. Inserted
in this lower forming die is a secondary ejector C which is
operated by plunger D. The upper member of this forging
tool consists of a punch-holder E carrying forming punch F
which is counterbored to receive an ejector ring G. Pass-
ing down through the center of punch F is a center-punch H
146
MAKING FUSE PARTS
that is made in two parts. The lower member is made of
high-speed steel, hardened, whereas the upper portion is
ordinary carbon steel. This center-punch is operated to
eject the forging by a plunger / on the up-stroke of the
press through the action of three pins J coming in contact
with the flange on punch H. K shows the rough casting
and L the completed forging.
Machinery
Fig. 4.
Diagram showing Construction of Tools for
forging Brass Plug
Tooling for Machining Brass Socket. The New Britain
automatic chucking machine, referred to in the following,
consists essentially of a multiple-chuck turret with capacity
for holding five or six pieces of work, acted upon simulta-
neously by four or five tool-holding spindles. The sequence
of operations is similar to that of a multiple-spindle screw
MAKING FUSE PARTS
147
machine. A finished piece is removed and a rough blank
inserted at each indexing. The machine is not idle while
chucking, there being one more chuck than spindles.
ADVANCE 0.022 PER REV. OF SPINDLES
PRODUCTION 120 PIECES PER HOUR
Machinery
Fig. 5. Diagram showing First Series of Operations on Fuse
Socket on the New Britain Automatic Chucking Machine
The shrapnel socket which, as previously explained, is
made from a brass casting and pressed into rough shape, is
machined in two settings in the New Britain No. 24 chuck-
148
MAKING FUSE PARTS
ing machine. This machine has four spindles, and at the
first spindle position, as shown in Fig. 5, reamer A cleans
out the hole in the pressed brass blank, counterbore B
cleans out the inside, and tool C faces the end. At the
ADVANCE 0.022 PER REV. OF SPINDLES
PRODUCTION 120 PIECES PER HOUR
Machinery
Fig. 6. Diagram illustrating Second Series of Operations on Fuse
Socket on New Britain Automatic Chucking Machine
MAKING FUSE PARTS
149
ADVANCE 0.025 'PER REV. OF SPINDLE
PRODUCTION 50 PIECES PER HOUR
Machinery
Fig. 7. First Series of Operations on Fuse Body on No. 73
Seven-spindle New Britain Automatic Chucking Machine
second spindle position, reamer D finishes the central hole,
counterbore E faces the bottom, and tool F chamfers the
hole.
150 MAKING. FUSE PARTS
The under-cutting preparatory to threading is done at the
third spindle position. The operation is performed with
tool G working on the cross-cutting head H. When the
pressed blank is fed in and reaches stop /, it commences to
push the housing H of the cross-cutting head backward.
A pair of stationary fingers J operate in oblique slots in
the housing H, and as the housing presses down on these
fingers, the motion gives a cross movement to the under-
cutting tool G and its arbor K. In this manner, the under-
cutting of the piece is performed. The fourth spindle
operation is simply that of tapping the threaded interior
with a tap L.
Second Operation on Shrapnel Socket. Fig. 6 shows
the order of operations performed on the shrapnel socket
at the second chucking, the work being screwed on threaded
arbors. At the first spindle position, pilot A engages the
central hole, while tool B turns the external diameter, tool
C chamfers the corner, tool D turns the thread diameter,
tool E faces the shoulder, and counterbore F finish-forms
the nose of the piece. At the second position, these same
surfaces are machined with finishing tools of the same
design as those just described.
At the third spindle position, the shoulder at the end of
the threaded section is under-cut. This is done by a cross-
cutting head, similar to that shown in Fig. 5 and carrying
the cutter G. At the fourth spindle position, the final oper-
ation threading is performed with die H.
Machining Fuse Bodies. In Fig. 7 is illustrated an in-
teresting tooling set-up for machining a fuse body. This
is done on the No. 73 seven-spindle New Britain automatic
chucking machine. The operations in this set-up are per-
formed on one end only of the fuse body. Strictly speak-
ing, this is a seven-spindle machine, but the first four spin-
dles carry internal spindles running at high speed that co-
operate with the external spindles in machining the work,
making this virtually an eleven-spindle machine. At the
first spindle position, the broad face and stem are machined
with cutters A of hollow-mill type, and centering tool B, car-
ried in the inner spindle, centers the work for drilling.
MAKING FUSE PARTS
151
In the second spindle position, tools C bevel the external
diameter of the flange at the same time that drill D is pro-
ducing the hole in the stem. In the third spindle position,
roll D supports the work against the thrust of beveling tool
E, and the small drill F held in the internal spindle deepens
the hole. At the fourth spindle position, the external spin-
dle carries a hollow-mill G that finishes the stem diameter,
and a counterbore H is carried in the internal spindle to
machine the central hole.
Fig. 8.
Machining a Shrapnel Head on the New Britain
No. 24 Automatic Chucking Machine
A cross-cutting head in the fifth spindle position carries
a circular tool / that machines on both sides of the section
subsequently to be threaded, and while this operation is
being performed the pilot J steadies the work as well as the
tool-holder. In the sixth spindle position, the small hole is
threaded with tap K, and the exterior is threaded with a
die, tap and die being of different pitches. In the seventh
spindle position, a holder carries the forming tool M for
152
MAKING FUSE PARTS
cutting grooves in the face of the flange, and the same spin-
dle carries a reamer N that finishes the hole in the stem.
Machining Steel Shrapnel Heads. Heads for shrapnel
shells made from cold-drawn steel stampings are machined
ADVANCE 0.0125 PER REV. OF SPINDLE
PRODUCTION 62 PIECES PER HOUR
Machinery
Fig. 9.
First Series of Operations on Shrapnel Head on the
New Britain Automatic Chucking Machine
in two settings on a No. 24 New Britain automatic chucking
machine of the four-spindle type, shown in Fig. 8. This
piece, shown in Fig. 9 in its sequence of operations, is espe-
cially difficult to machine on account of the stringy nature
of the metal. The work is held for the first chucking with
MAKING FUSE PARTS
153
ADVANCE 0.0125 PER REV. OF SPINDLE
PRODUCTION 90 PIECES PER HOUR
Machinery
Fig. 10. Second Series of Operations on Shrapnel Head on the
New Britain Automatic Chucking Machine
the small end out, and in the first spindle position the fac-
ing on the end is distributed between tools A and B, while
counterbore C roughs out and chamfers the hole. In the
second spindle position, tool D faces the end, and counter-
bore E finishes the hole. A cross-cutting head of a type
similar to that previously described is carried in the third
154
MAKING FUSE PARTS
spindle position. This retains a tool F which produces an
annular groove in the nose of the head, the work being sup-
ported with pilot G. The fourth and last operation consists
in threading the hole with the tap H.
ADVANCE 0.0167 PER REV. OP SPINDLE
PRODUCTION 225 PIECES PER HOUR
Machinery
Fig. 11. Diagram showing Tooling Set-up for machining Fuse Nose
on New Britain Automatic Chucking Machine
MAKING FU$E PARTS
155
ORMING TOOL
1ST OPERATION
SELF-OPENING DIE
NTERNAL
NECKING TOOL,
2o OPERATION
3D OPERATION
2o OPERATION
FIRST SERIES OF OPERATIONS
3D OPERATION
SECOND SERIES OF OPERATIONS
Fig. 12. Machining Brass Fuse Socket on 3^/ 4 -inch "Gridley"
Automatic Turret Lathe First and Second Series of Operations
Second Series of Operations on Shrapnel Heads. The
set-up for the series of operations performed at the
second chucking is shown in Fig. 10, the work being held
156 MAKING FUSE PARTS
on threaded arbors. In the first spindle position, tools A
and B face the shoulder, and counjerbore C machines a
seat in the inner flange. In the second spindle position,
counterbore D finishes the part roughed out by C in the
previous operation, tool E faces the end, and tool F cham-
fers the inner edge. In the third position, a cross-cutting
attachment carrying external cutting tool G is utilized for
recessing the external diameter next to the shoulder. The
threading on the external diameter is accomplished with
the die H in the fourth spindle position.
Machining Shrapnel Fuse Noses. The time fuse nose
for a shrapnel shell, which is made from a brass forging, is
machined as shown in Fig. 11 on a No 33 New Britain
automatic chucking machine at one setting. It this case,
an extra spindle designated as No. is added to the machine
for equalizing or properly locating the forging in the chuck
when it is being tightened. At the first spindle position,
tool A takes a cut from the external diameter, tool B cuts
an annular recess in the face, and counterbore C roughs out
the center portion. In the second spindle position, the same
operations are performed with finishing tools. In the third
spindle position, a cross-cutting head carries a recessing
tool D that forms a recess back of the tapped portion. The
hole is then tapped in the fourth spindle position, and in the
fifth spindle position a special counterbore F takes a light
finishing cut from all the surfaces previously machined.
The external surfaces of the fuse nose are, machined on a
turret lathe.
Machining Shrapnel Fuse Parts on "Gridley" Automatics.
The machining of fuse parts for the British shrapnel
shell on "Gridley" single- and multiple-spindle automatics,
made by the Windsor Machine Co., Windsor, Vt., forms the
basis of several interesting tooling equipments. A num-
ber of the parts are machined from hot-pressed brass forg-
ings, so that they must be handled separately. The fuse
socket, as has been previously described, is made from a
brass forging and is machined complete in two operations
on a 3% -inch "Gridley" automatic turret lathe of the single-
spindle type. The manner in which the work is loaded in
MAKING FUSE PARTS
157
ORMING TOOL
SECOND SERIES OF OPERATIONS
FIRST SERIES OF OPERATIONS Machinery
Fig. 13. Diagram illustrating First and Second Series of Operations
on Fuse Body on "Gridley" Automatic
158 MAKING FUSE PARTS
the chuck and held for the first series of operations is
shown at A in Fig. 12. The rough blank a is first placed
over the spring fingers b, which are held in a holder clamped
in the turret, but are free to rotate. When the work is
pushed into the chuck, it forces back spring-ejecting stud
c, which, as soon as the pressure of the chuck is released,
ejects the work.
As the loading device operates on the first slide of the
turret, the first machining operation takes place on the
second slide. This is a comparatively simple operation and
consists in boring the central recess with a tool d and cham-
fering with tool e. The turret is then indexed, bringing the
internal necking tool / into position. This is held in a
holder and is operated by the forward motion of the forming
slide. Following this, tap g is brought into position to
thread the recess in the socket. The operation of the tur-
ret is now stopped automatically until the operator loads a
new piece in the chuck. The tapping is done with the spin-
dle running in the forward direction on slow speed. After
the hole has been tapped, the spindle is reversed and oper-
ated at a higher speed. The spindle continues to run back-
ward for loading, and is still running backward, but slowed
down, at the time of the second operation. It is for this
reason that the boring tool d operates on the reverse side
of the hole, and tool e is mounted upside down. At the
third operation, the spindle is still running backward but
is speeded to its highest speed while the internal necking
is done with the tool on the reverse side of the hole.
Second Operation on Fuse Socket. The method of hold-
ing the fuse socket for performing the second operation on
the 3 14 -inch "Gridley" single-spindle automatic turret lathe
is shown at B in Fig. 12. The socket h, which has now
been threaded, is screwed onto the body of special arbor i,
fitting in sleeve j that is gripped by the spring collet. On
the reduced end of arbor i is a nut which serves to clamp
the work up against the face of sleeve j. The method of
using this arbor is as follows:
To chuck the work, sleeve j and its auxiliary members are
removed from the spring collet, and the work is screwed
160 MAKING FUSE PARTS
position and back to slow just before the fourth position.
Machining the Fuse Body. The fuse body is made
from a hot-pressed brass blank, and is machined in
two chuckings in "Gridley" multiple-spindle automatics.
The first series of operations is performed in a "Gridley"
1%-inch multiple-spindle automatic in the order shown to
the left in Fig. 13. The work is loaded in the chuck by
hand. Forming tool A now advances and rough-forms the
outer diameter, whereas flat drill B and trepanning tool C
combine to drill the central hole and trepan the narrow
channel. At the second spindle position, tool D finish-
forms and necks the outer surface, while tool E counter-
bores the surfaces of the recess. Die F at the third spindle
position now threads the body, and at the fourth spindle
position forming tool G turns down the outer end of the
thread while a floating trepanning tool H finishes the coun-
terbored and trepanned surfaces. It should be mentioned
here that the hot-pressing of this brass part makes it ex-
tremely difficult to machine, so that the edges of the tools
dull rapidly.
Second Series of Operations on Fuse Body. The method
of holding the fuse body while the second series of opera-
tions is being performed is shown in Fig. 14. The work-
spindles A of the machine are fitted with special nose-pieces
B, the inner surface of which is chamfered to receive the
spring collet C, which is threaded to the end of draw-back
rod Z>. The work is not gripped directly by the spring
collet, but is first screwed into a special bushing E, having
thin walls as shown. This bushing is not split but springs
sufficiently to permit it to be closed in on the work and
released when the collet pressure is removed. A flange G
attached to the end of the spindle nose serves as a stop for
the work and a gaging point for the operations. The
regular collet closing mechanism is used, but as may be seen
in the left-hand end, the finger holders are reversed. When
the clutch ring H is pushed forward by the chuck-closer
gripping fingers / swivel and draw rod D backward through
contact with flange /. When the clutch ring H is moved
MAKING FUSE PARTS
161
FORMING TOOL
PILOTED
COUNTERBORING
AND FACING TOOL
Machinery
Fig. 15.
Diagram illustrating Set-up for machining Timing
Train Rings on "Gridley" Automatic
backward, the gripping fingers release rod D, relieving the
pressure of the collet on bushing E and the work.
Referring again to Fig. 13, the second series of operations
on the fuse body is shown to the right of the illustration.
At the first spindle position, forming tool / advances and
forms the exterior diameters, while drill / drills the hole
162 MAKING FUSE PARTS
in the end. At the second spindle position, the rear part of
the work is supported by a roll back-rest, while the regular
turner K takes a cut across and chamfers the shoulder. At
the same time counterbore L comes in, cleans up the drilled
hole and faces the bottom. At the third spindle position,
the diameter M is threaded with a plain die. At the fourth
spindle position, a tool N operated from the turret cuts a
series of concentric grooves in the flange of the fuse body.
The grooving tool is cut away to clear the forming tool O
which takes a light cut over the grooved face, finishing the
body as illustrated.
Machining the Stationary Timing Train Ring. The
machining operations on the stationary timing train ring
are shown to the left in Fig. 15, and as can be seen are of
a comparatively simple nature. This fuse part is made
from a Tobin bronze bar in a 2% -inch "Gridley" multiple-
spindle automatic. At the first spindle position, a drill
held on the turret drills the hole, and a forming tool on the
cross-slide forms it to shape and breaks it down for the
cut-off tool. At the second spindle position, the piece is
reamed, and at the third position it is faced off with an
under-cutting tool. In the fourth spindle position, not
shown, the finished piece is cut off, and the stock is fed out.
Machining the Graduated Timing Train Ring. The
machining operations on the graduated timing train ring
are almost identical with the stationary ring and are shown
diagrammatically to the right in Fig. 15. This part is also
made from a bar of Tobin bronze in a 2%-inch "Gridley"
multiple-spindle automatic. The only difference in the op-
erations on this part is in the use of a combination float-
ing counterbore, and facing tool provided with a roller pilot.
Machining the Closing Cap and Bottom Closing Screw.
The closing cap and bottom closing screw for the shrap-
nel timing fuse are made from brass rod with a compara-
tively simple tool set-up as shown in Fig. 16. The machine
used is a 1%-inch "Gridley" multiple-spindle automatic.
The machining operations on the closing cap are shown to
the left in the illustration, and consist in drilling, counter-
boring, forming, threading, and cutting off. The opera-
MAKING FUSE PARTS
163
COUNTERBORE
\
FORMING TOOL
FLAT FORMING TOOL.
CUTTING-OFF
TOOL
CUTTING-OFF
'TOOL
Machinery
Fig. 16. Diagram illustrating Set-ups for machining Closing Cap
and Bottom Closing Screw on "Gridley" 1%-inch
Multiple-spindle Automatic
164
MAKING FUSE PARTS
tions on the bottom closing screw, shown to the right of
this illustration, are counterboring, forming, recessing,
threading, and cutting off.
FEED STOCK TO STOP
*/
DRILL BOTTOM HOLE
REAM AND "BOTTOM" HOLES
CUT-OFFTOOL ON
BACK SLIDE
Machinery
Fig. 17. Method of machining Fuse Hammer on a No. 2 Model G
Brown & Sharpe Automatic Screw Machine equipped with
-an Eight-hole Turret
Making Fuse Parts on Brown & Sharpe Automatic and
Hand Screw Machines. A brief description of two of the
many interesting set-ups on Brown & Sharpe automatic
and hand screw machines for making timing fuse parts
MAKING FUSE PARTS
165
is given in the following 1 . Timing fuse parts are made
from several different materials. The screws and other
small members as a rule are made from brass rod, whereas
the parts such as the capsules, primer cups, etc., are made
from sheet brass. Other members, such as the fuse body
FORM AND CUT-OFF
ERTICAL SLIDE TOOL
Machinery
Fig. 18. Diagram illustrating Method of Machining a Fuse Nut on a
No. 6 Brown & Sharpe Hand Screw Machine
or stem, are made from different alloys and metals such as
copper, copper aluminum, aluminum, etc.
Set-up for Making Fuse Hammers. The method of
making a fuse hammer on a No. 2 Model G Brown & Sharpe
automatic screw machine provided with a special eight-hole
turret is shown diagrammatically in Fig. 17. This part is
166 MAKING FUSE PARTS
made from %-inch round brass rod and is finished com-
plete in the screw machine. First, the stock is fed out to
the stop in the turret. Second, the end is centered and
faced with tools held in tool-holder A. The body is then
formed with a circular tool B working from the front cross-
slide ; at the same time the turret is revolved, bringing tap
drill C into operation. The forming tool is working at the
same time as the drills. The turret is again revolved and
drill D for finishing the middle hole is brought in and com-
pletes its operation. At the next index of the turret, drill E
finishes the bottom hole. The turret is now indexed and a
recessing tool-holder carrying tool F advances and is
brought into operation to recess the work by a pusher on
the cross-slide. The turret is again indexed and a reamer
G is advanced to bottom and ream the holes. Upon the
next index of the turret, tap H threads the work, which is
finally cut off with circular tool /. The stock is rotated at
973 R. P. M. forward and backward for drilling and turn-
ing, and at 421 R. P. M. forward for threading. The stock
is cut off rotating backward. The surface speed for the
forming tools is 220 feet per minute and 31 feet per minute
for the tap.
Tool Set-up for Making Fuse Nut. The fuse nut on
the Russian timing fuse is made from 1 %-inch round
brass rod in a No. 6 wire-feed Brown & Sharpe hand-screw
machine as shown in Fig. 18. First the stock is fed out
to length, being gaged by a stop in a vertical slide, which
is held in the turret. The turret is then indexed and drill
A drills the large hole. The turret is now revolved and the
combination drill B is advanced. The turret is again re-
volved and counterbore C faces and counterbores the work.
Upon the next index of the turret, a vertical slide tool-holder
carrying recessing tool D is advanced. This tool-holder is
operated by a handle attached to the holder. The turret is
again indexed and tap E threads the work. After this the
turret is indexed and the work is recessed with a tool-holder
F carrying two cutters which balance each other in cutting.
The seventh operation is performed from both the front
and rear cross-slides with tools G and H. The eighth oper-
MAKING FUSE PARTS 167
ation is cutting off. This is performed with a special verti-
cal slide tool-holder held in the turret and operated by a
handle. The stock for these operations is rotated at 352
R. P. M., giving a surface speed for the forming tools of
180 feet per minute and 66 feet per minute for the tap.
Making Fuse Parts on Hand Screw Machines. The de-
mand for shrapnel fuse parts has been so great that time
has not been taken in all cases to tool up automatic screw
machines before production has been started. In order to
get parts out quickly while automatic machines are being
tooled up, hand screw machines have been made use of.
Fig. 19. Machining Fuse Parts on F. E. Wells & Son's
Hand Screw Machine
These machines are also used to a large extent on small
orders and to help out production in general. Fig. 19
shows an F. E. Wells & Son Co. hand-screw machine work-
ing on shrapnel fuse parts. The capacity of this machine
is for %-inch diameter rod and it will tap or drill % inch
diameter. Shrapnel fuse parts are produced on this ma-
chine at the rate of from 25 to 100 pieces per hour.
Drilling Percussion Primers for Fuses. The percussion
primer, used in the American combination fuse shown in
Fig. 3, Chapter I, is made in a Brown & Sharpe automatic
screw machine from brass rod in two operations. Follow-
168 MAKING FUSE PARTS
ing the screw machine operations, four holes about 1/32
inch in diameter are drilled through this bushing, employ-
ing a special "snap index" jig in a high-speed ball-bearing
drilling machine made by the Leland-Gifford Co. of Wor-
cester, Mass. (See Fig. 20.) The extremely small size of
this part makes it difficult to handle, so the jig was designed
Fig. 20. Drilling Percussion Primers on a Leland-Gifford Ball
Bearing Sensitive Drilling Machine
with a special loading arm to facilitate rapid handling.
The jig consists of a platform base bolted to the table of
the drilling machine. Upon this is the index ring, which is
turned by handles / and indexed for the four drilling posi-
tions by spring plunger /. The center of rotation is in
the center of the four holes in the part. B is the loading
MAKING FUSE PARTS
169
lever, with a nest A at the end into which the work is slip-
ped. This lever swings on stud C. The work is located
in the swinging arm B when it is in the position shown in
the illustration, with the arm B resting against stop D.
The arm is then swung under the drill until it reaches stop
E. It is maintained in this position by spring plunger H
that bears against lever F, fulcrumed on stud G. The side
of this lever bears against the work and holds it firmly
Fig. 21. Drilling Fuse Plugs on "Avey" Drilling Machine
while the drilling is proceeding. The drill is guided by
four bushings in plate L, mounted on the index ring. The
operation consists in rotating the index ring to the four
stations for drilling the respective holes. By means of this
quick-indexing ring, and the high speed at which the Leland-
Gifford drilling machine runs, it is possible to drill as many
as 6000 pieces, or 24,000 holes in ten hours.
170
MAKING FUSE PARTS
Drilling Timing Fuse Plugs. An application of a regu-
lar No. % "Avey" drilling machine, built by the Cincinnati
Pulley Machinery Co., Cincinnati, Ohio, to the drilling of
brass timing fuse plugs is shown in Fig. 21. The require-
ments are to drill three No. 55 (0.052 inch) holes through
the dome of the plug ; a number of pieces are shown on the
table of the machine.
These three holes
practically run to-
gether at the inside
of the dome, making
it necessary to drill
one hole at a time.
The fixture used for
this purpose is of
unique construction.
The body A is made
of an aluminum cast-
ing, whereas the
operating mechanism
is of hardened tool
steel. The drill spin-
dle is operated by a
foot treadle, connec-
tion being secured
through rod B, pass-
ing down through
the fixture and fast-
ened to the spindle
sleeve by the L-
shaped piece and
yoke C. The work E
i^ij -_ Q C rm/ial
work-spindle located
inside the fixture that is indexed one-third revolution
through the medium of rod B upon the raising of the drill
spindle sleeve. The work holding-down and ejecting
mechanism is supported in aluminum bracket F. Attached
to this bracket is a supporting arm for the lower crank of
Fig. 22. Graduating Timing Fuse Rings
on Dwight-Slate Marking Machine
MAKING FUSE PARTS 171
lever G, which holds a segment gear. Bracket D carries
the drill bushing.
After drilling the third hole, the operator depresses lever
G, rotating the segment gear meshing in rack teeth in rod
H, which lifts the latter up to eject the work and at the
same time through a connection, not shown, raises the
holding-down rod. The ejector, not shown, which is spring
controlled, returns to a neutral position immediately upon
the ejection of the work, while the holding-down rod is still
raised. The work, after being discharged, falls into a chute
and is carried to the rear of the machine. The operation
of this fixture is rapid, the production being from 9000 to
10,000 pieces in ten hours.
Graduating Fuse Timing Ring. As has been previously
stated, the adjustable ring on the timing fuse is graduated
in seconds, starting at zero and running to twenty-one sec-
onds. As shown in Fig. 22, the graduating of this timing
ring is performed in the Dwight-Slate marking machine
built by Noble & Westbrook, Hartford, Conn. The main
arbor of the machine carries the stamping roll A and is
turned by the handle shown. The timing ring to be grad-
uated and marked is held at B. The two gears C prevent
the stamp from "creeping" ahead or slipping on the work.
The work-holding arbor, as shown, is held in a bracket and
is raised to the stamp roll by pressure on the foot treadle.
Two operations are required for stamping and graduating
the timing ring. The first is marking the graduations and
the second is putting on the figures.
CHAPTER VI
MAKING SHRAPNEL CARTRIDGE CASES
THE brass cartridge case that contains the powder
charge for propelling the shrapnel shell from the bore of
the quick-firing gun is drawn up from a blank of sheet
brass. The number of operations necessary to complete the
case depends on its size and the method of handling. Some
shell manufacturers prefer to do more or less drawing at
one operation, but in all cases the sequence of operations
is practically the same. The material used for shrapnel
cartridge cases generally consists of a composition of 2
parts copper and 1 part zinc. This alloy has been found to
possess the best physical qualities, that is, great tensile
strength and a high percentage of elongation when properly
annealed. The drawing operations through which the cart-
ridge case passes increase the hardness, and the ductility of
the metal is restored by annealing. The annealing temper-
ature in most cases is from 1150 to 1200 degrees F. On
reaching this temperature, the work is either cooled off in
water or allowed to cool off gradually, as the speed of cool-
ing does not affect its physical qualities. In the following,
two methods of handling the various operations will be de-
scribed.
Method of Making Cartridge Cases. Figs. 1 and 2
show the sequence of operations blanking, cupping, re-
drawing, indenting, trimming, heading, and tapering, as
advocated by the Waterbury Farrel Foundry & Machine
Co., Waterbury, Conn., for making cartridge cases for 18-
pound shrapnel. The first operation consists in cutting out
a blank from %-inch sheet brass 6% inches in diameter.
The next operation is cupping. This is handled in a short-
stroke geared straight-sided press. Before re-drawing, the
cup is annealed, and the third operation, which is handled
in a longer stroke press, is then performed. Annealing fol-
lows this operation, and then the fourth drawing or second
re-drawing operation is performed. This consists in re-
172
CARTRIDGE CASES
173
Mr *
20 OPERATION-CUP
k 1J4 11 ^
3o OPERATION 1sT DRAW
4TH OPERATION-20 DRAW
STH OPERATION- 1iT INDENTING
4" -+-K'
%
6TH OPERATION 2o INDENTING
&'
H 4- >i
7TH OPERATION-3D DRAW
M v *"4
k= y^. 51
I I
STH OPERATION 4TH DRAW
10TH OPERATION
CUT Off ENO
DF CASE
&TM OPERATION-DTH DRAW
Fig. 1. Operations in making an "18-pound'
Cartridge Case
174 CARTRIDGE CASES
ducing the fillets slightly at the corners, decreasing the
diameter of the cup to 4% inches and increasing its length
to 4% inches. The dimensions given here are approximate.
Indenting Operations. --The fifth operation or first in-
denting operation, which consists in indenting the bottom,
is handled in a press similar to that used for the cupping
and re-drawing operations. This shortens the length of
the case by % inch and forces the indentation about half
way through the thickness of the stock. The second in-
denting is then accomplished. This again shortens the
case by an additional 14 inch and squares up the corners.
The case, without annealing, is now passed through the
third re-drawing, or seventh, operation, reducing its diame-
ter to 4 inches and increasing its length to 5i/ 2 inches. It
is annealed after this operation, and is then drawn to a
shape 8 inches in length by 3% inches in diameter, and the
wall decreased in thickness to 1/16 inch. The case is then
annealed and passes through the fifth re-drawing operation.
The machine used for handling the third, fourth and fifth
re-draws is a long-stroke straight-sided rack-and-pinion
press. After the fifth re-drawing, or ninth, operation, the
case is trimmed and about two inches cut off the end. This
leaves the case in better condition for the succeeding oper-
ations. The trimming machine is of the horizontal type.
Final Re-drawing Operations. The sixth re-drawing,
or eleventh, operation is performed in a horizontal drawing
press of the hydraulic type provided with automatic revers-
ing valves. This operation increases the length of the case
to 13*4 inches and reduces its diameter to 33/4 inches.
After this operation, the case is annealed and then 1% inch
is trimmed off the open end. The thirteenth and fourteenth
operations consist in heading the case. These are practi-
cally of the same nature, and combine to form the head of
the case as shown in the illustration. The heading opera-
tions each reduce the length of the case 1/4 inch, and are
performed in a 1000-ton hydraulic heading press operated
by a geared compound power pump and having a working
pressure of 5600 pounds per square inch on the ram. After
heading, the case is annealed and the fifteenth operation,
CARTRIDGE CASES
175
,12rn OPERATION
TRIM CASE
12-INCH LONO
T
k %- ?!
11TH OPERATION-6TH DRAW
-Jt IR-ru ODCDATI/Mu 1 ** TAO
M OPERATION-18T TAPERING
17TH OPERATION
TIM OFF V4"
,13TH AND
UTH OPERATIONS- HEADING 16TH OPERATlON-2o TAPERING
Fig. 2. Operations in making an "18-pound'
Cartridge Case
176 CARTRIDGE CASES
which consists of tapering, is performed. The first taper-
ing, or fifteenth, operation reduces the mouth of the case
to 3 9/16 inches in diameter and gradually tapers it for a
distance of 5% inches half the length. The case is then
annealed, pickled and washed, and a second tapering opera-
tion is performed. This reduces the mouth of the case to
3% inches and tapers it completely to the head. The case
is not annealed after the last tapering operation, but 1/4
inch is trimmed off the end.
The various operations through which a cartridge case
passes in drawing and forming to the correct length having
been described, attention will now be given to the type of
tools used for this purpose. These tools have been designed
and built by the Ferracute Machine Co., Bridgeton, N. J.,
and are used with its presses for making cases for 3-inch
projectiles.
Cupping and First Series of Re-drawing Tools. The
cutting out of the blank is frequently omitted because the
specified thickness and size can be furnished by the mill.
Before cupping, the dies and blanks are well greased, as this
assists in drawing. Olive oil or soapy water is used, de-
pending on the stage at which the drawing operations have
arrived. The first cupping operation is accomplished with
a punch and die as shown at A in Fig. 3. This operation
is accomplished in a Ferracute 100-ton ram press equipped
with a dial feed. The die consists of a hardened ring of
tempered steel having an interior shape similar to a trun-
cated cone. The punch is slightly tapered on the lower end
and has an air vent hole drilled up through it to facilitate
the drawing and produce a cup free from wrinkles.
The second operation, or first re-drawing operation, is
shown at B. Here the type of die used differs somewhat
from that shown at A, in that the drawing angle is 15 in-
stead of 45 degrees. The cup, after this operation, is re-
duced in diameter to 3.877 inches and is 2% inches long.
After the first cupping operation, the case is annealed.
The second re-drawing operation is accomplished as shown
at C. The die in this case is the same as at B, as is also
the punch, except for an increase in the taper and change
CARTRIDGE CASES
177
I_OL | CO _oj'
! OT.'T '~5
5TH DRAW HORIZONTAL SCREW PRESS
Machinery
Fig. 3. Tools for drawing a 3-inch Shrapnel Cartridge Case
Ferracute Machine Co.'s Method
in shape on the end. The object of this, of course, is to
keep the case thick at the head but reduce the walls further
up along the section. The case, after this operation, is also
drawn out to a length sufficient to necessitate using a strip-
178 CARTRIDGE CASES
ping device for removing it from the punch. This is accom-
plished by six spring-operated stripper pins as shown, which
slip over the top edge of the case as it is forced through the
die, stripping it from the punch. The cup now passes
through the third annealing operation and is ready for the
third re-draw, shown at D. The press used for performing
this operation is similar to that described, and the die and
punch is similar in construction to that shown at C.
Final Re-drawing Operations. For the final re-drawing
operations, horizontal double-ended screw presses instead of
the horizontal hydraulic presses formerly used are em-
ployed. Horizontal presses are used because the length to
which the cartridge case is drawn after the third re-draw
is such that it exceeds the stroke of the vertical presses.
The cartridge case, after each drawing operation, is an-
nealed; E in Fig. 3 shows the fourth re-drawing tools,
which are handled in a horizontal screw press. The die
used is similar in shape to that shown at D, but the holder
in which it is held differs, of course, owing to the difference
in the type of press used. The stripping arrangement for
removing the case from the punch is also of a different type.
In this case five spring-operated stripper pins are held in a
holder which is free to oscillate within certain limits in
the block in which it is retained. The reason for having
this oscillating stripper is that it accommodates itself to the
irregular shape on the end of the case and gives practically
a constant pressure all around the circumference of the
case, assisting in removing it from the punch. The case
is now annealed and is finish-drawn as shown at F. Here
the same type of die, stripper arrangement, etc., is used as
that shown at E. The case in the fifth re-drawing opera-
tion is 14% inches long by 3.186 inches outside diameter.
Annealing and Washing Cartridge Cases. As was pre-
viously stated, the cartridge case, after practically every
re-drawing operation, is annealed, being subjected to a tem-
perature of about 1150 to 1200 degrees F. and then allowed
to cool off or dipped in water which, of course, forms a scale
on the surface of the case. This must be removed before
any subsequent operations can take place. Several differ-
CARTRIDGE CASES
179
ent solutions are used for this purpose, but a common one
comprises the following : Sulphuric acid diluted with water
to a strength of 1 to 4. This pickling solution is held in
lead-lined wooden troughs and the case is allowed to remain
in the bath varying from eight to fifteen minutes, accord-
ing to the strength of the solution. The cases are then
washed in lead-lined wooden troughs through which a stream
of water is circulated to remove all traces of the acid.
Testing Hardness of Cartridge Cases. The hardness of
a cartridge case must conform to a certain standard. When
too soft, a permanent set will occur from the pressure of
Machinery
Fig. 4. Fixture for testing Hardness of Cartridge Cases with
Shore Scleroscope
the firing charge and the case will stick in the breech of
the gun. When the hardness is too high for a given com-
position of brass, it is too brittle and will split, or the
head may blow off. There is, therefore, a certain hardness
which must be adhered to as closely as possible. Some
manufacturers hold the standard to within 20 to 25 on the
body walls and reject cases striking 15 as being too soft,
and 30 to 35 as being too hard.
Owing to the thinness of the walls of the case, it is im-
possible to take a reading without rigidly supporting it,
and for this purpose the Shore Instrument & Mfg. Co.,
180
CARTRIDGE CASES
551-557 West 22nd St., New York City, has devised a spe-
cial fixture as indicated in Fig. 4. This comprises a bracket
A held in an ordinary vise, to which is fastened an anvil
plug B, as indicated. In order to hold the case tightly
against the anvil plug, a spring C, fastened to the bracket A,
is also fastened to a yoke D surrounding the case. A rod
attached to the yoke and to a foot treadle furnishes a means
of drawing the yoke down to hold the case in contact with
the plug. The anvil plug provides the weight or inertia to
Fig. 5. Special Shrapnel Case Trimming, Facing, and
Chamfering Machine
resist the impact of the drop-hammer of the scleroscope,
but in order to be sure that there is proper contact of the
case with the plug a rubber cushion E is provided between
the pressure ring or yoke and the brass case.
Machining Shrapnel Cartridge Cases. The Bullard Ma-
chine Tool Co., Bridgeport, Conn., has designed and built
a number of special machines for performing the machin-
ing work on the head and mouth ends of brass cartridge
CARTRIDGE CASES
181
6TH OPERATION
Machinery
Fig. 6. Sequence of Operations performed on Cartridge Case in
Machine shown in Fig. 5
cases. This machine, as will be seen from Fig. 5, is of the
hand turret machine type, designed to work on the case
from both ends. In this machine the brass case is chucked
in the center of an extremely large spindle, and worked
on from the head end with four sets of turret tools and two
sets of cross-slide tools, while the mouth end is bored and
182 CARTRIDGE CASES
trimmed with tools held on a carriage located on the back
facing bar. The drive for the work chuck spindle is over
a 16-inch pulley with a 3-inch belt. The pull of the belt is
not taken directly on the spindle, but on a special pulley
bearing 7% inches in diameter and 5 inches in width. The
spindle itself is supported in bearings 9 inches in length
and 5% inches in diameter. As previously mentioned, the
spindle is hollow so that any type of shrapnel cartridge case
up to 414 inches in diameter and from 10 to 18 inches in
length can be machined.
Fig. 7. Set-up showing First Operation on Cartridge
Case Head
From the construction of the machine in Fig. 5 it will
be seen that the front end of the spindle carries a large
three-jaw chuck of special design. These jaws catch the
cartridge case just under the head and revolve it for ma-
chining. The case is supported internally by a tubular
arbor which also acts as a stop and is attached to a rod
extending to the rear bracket where it is backed up by a
spring. The front end of this tubular support or stop
is provided with a thrust ball bearing so that the case can
be loaded in the chuck while the spindle is running. When
the chuck operating lever is manipulated to close the chuck
jaws on the work, it first draws back the rod mentioned
CARTRIDGE CASES
183
through the medium of a tie-rod and the rear bracket to a
positive stop, and then closes the jaws on the work. The
cartridge case is put in and removed from the chuck with
Fig.
Set-up showing Fourth Operation on Cartridge
Case Head
Fig. 9. Set-up showing Operations on Mouth End of Case
the turret indexed between stations to give the required
space.
The back boring and trimming head is held on a hollow
spindle through the center of which the rod passes. This
184
CARTRIDGE CASES
spindle is provided with rack teeth on its top surface
which engage with a pinion located in the extension bracket
and operated by a handle. The forward position of the
boring and trimming head is governed by a stop-collar.
Fig. 10. Set-up showing Sixth Operation on Head End of Case
Fig. 11. Set-up showing Seventh Operation on Head
End of Case
Sequence of Machining Operations on Cartridge Case.
-The sequence of machining operations performed on the
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186
CARTRIDGE CASES
The following operations are now performed on the mouth
or open end of the cartridge case as shown in Figs. 6 and 9,
with the spindle running at the same speed 500 R. P. M.
as that used for the first series of operations. Two tools
H and / are used. Tool H bores the mouth of the case for
a distance of 1 inch, whereas tool / trims off the open end
of the case and rounds the edges. The mouth of the case
at the rear end of the spindle is supported by a hardened
4TH OPERATION
FRONT CROSS-SLIDE BLOCK
2ND OPERATION
Machinery
Fig. 13. Diagram illustrating Machining Operations on French
Cartridge Case on Potter & Johnston Machine
bushing to prevent it springing away from the action of
the boring tool. The boring and trimming tools are
mounted in a special head J, Fig. 9, that is operated back
and forth by a handle K through the medium of a rack
and pinion. The forward movement of this head, as
previously explained, is controlled by means of an adjusta-
ble collar L screwed onto spindle M.
CARTRIDGE CASES
187
The work-spindle is now slowed down and the following
operations, shown in Figs. 6, 10, and 11, are performed on
the head end of the case. The sixth operation is to finish-
counterbore and ream the primer pocket with tool O held
FIRST
OPERATION
THIRD
OPERATION
RECESSING TOOL
SIDE
ELEVATION
CAM ON CROSS-SLIDE
""" FOR OPERATING
VERTICAL SLIDE TOOL
Fig. 14.
Tooling Set-up for Machining 18-pound
Cartridge Case
in an adjustable holder, whereas the seventh operation is
threading the primer pocket with collapsible tap P. The
chuck lever in Fig. 5 is now manipulated, first, releasing
the grip of the chuck jaws on the case and, second, advanc-
188
CARTRIDGE CASES
ing the rod to eject the case sufficiently to enable it to be
easily removed from the chuck. The spindle is changed
to the highest speed after the next case is put in. In
changing the work, it is not necessary to stop the spindle.
Machining Shrapnel Cartridge Cases on Potter & Johnston
Automatics. The cartridge case is made from sheet brass
as previously stated. It is practically formed to shape in
drawing and heading machines, but to secure the desired
accuracy on the head and primer pocket these surfaces are
Fig. 15. Tool Set-up for Machining 18-pound Cartridge Case
machined. The method of holding the French 75-milli-
meter case on a No. 5A Potter & Johnston automatic chuck-
ing and turning machine for machining the head and primer
pocket is shown in Fig. 12. Here it will be seen that the
cartridge case butts up against a stop B and fits over the
tapered plug C, which steadies it. It is held in place by an
ordinary draw-in collet D. This is operated by means of
a lever E, fulcrumed to a bracket on the rear end of the
machine and operating a sliding clutch collar. The chuck
CARTRIDGE CASES 189
is operated through fingers which draw back the sliding
sleeve to which it is attached. These fingers operate
against a spring at the rear of the spindle which serve to
open the collet.
The machining operations on the French shrapnel cart-
ridge case are handled in the manner illustrated in Fig. 13.
The first operation is to rough-drill the hole in the head.
The turret is then indexed, bringing in a roughing reamer
which reams the hole previously drilled, whereas the front
cross-slide carries tool B that faces the head and a circular
tool C that rough-forms the external diameters of the head.
Upon the next indexing of the turret, the tool D counter-
bores the powder pocket and the circular forming tool E
finish-forms and rough-chamfers the head. The last oper-
ation consists in finishing the primer pocket with a taper
reamer F.
Machining the British Shrapnel Cartridge Case. The
brass cartridge case for the British shrapnel is more
difficult to machine than the French case, as refer-
ence to Figs. 14 and 15 will clearly show. The machining
operations are accomplished on a No. 5A Potter & Johnston
automatic chucking and turning machine having a five-
sided turret. The first operation is to drill the primer
pocket hole with a three-step drill A. The turret is now
indexed and the surfaces previously roughed out are fin-
ished with inserted-blade counterbore B. At the same time,
the head of the case is faced with a relieving tool C held on
the cross-slide and rough-formed with circular tool D.
The turret, in being indexed to the third position, brings
vertical recessing tool E into operation. This carries two
cutters, one of which recesses the primer pocket at the
point where the thread is to terminate, whereas the other
removes the burr and faces the inner boss. In the fourth
operation, the smallest diameter of the primer pocket is
reamed and the largest diameter of the hole chamfered by
tools held in bar F. The rear cross-slide is advanced at
the same time, carrying the circular tool G that finish-forms
the head. The final operation threading is performed
with the "Geometric" collapsible tap H.
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191
192 CARTRIDGE CASES
Summary of Operations on Cartridge Cases. The ac-
companying table gives a summary of the cupping, drawing,
annealing, indenting, trimming, heading and machining op-
erations on a British 18-pound cartridge case of a compo-
sition of 70 parts electrolytic copper and 30 parts Bertha
spelter. In the plant where this information was obtained,
the cupping, indenting, and first, second, third, and fourth
redrawing operations are accomplished on bulldozers, while
the fifth and sixth redrawing operations are accomplished
on a frog and switch planer from which the cross-head has
been removed and a special fixture substituted in its place.
The punch is held rigidly in this fixture and the die on an-
other fixture clamped to the table of the planer. Practi-
cally the same condition prevails on bulldozers. Here the
punch is held rigidly, whereas the die is held in the travel-
ing slide. As a lubricant for drawing a compound known
as "viscosity," manufactured by the Cataract Refining Co.,
is used throughout, except on the fourth and fifth redrawing
operations, where ordinary commercial vaseline has been
found to give the best results.
The annealing is done in a Quigley oil furnace, which
is kept at a constant temperature of between 1100 and 1140
degrees F. The cups are handled in sheet iron boxes with
wire bottoms carrying 140 cups. This furnace holds seven
of these boxes ; it requires 35 minutes for one lot of cups to
pass completely through the furnace. In other words, a
box is put in and taken out every five minutes, thus giving
an annealing time of thirty-five minutes on each batch.
After dipping in water, the cups are immersed in a weak
solution of sulphuric acid to remove all scale.
Scleroscope readings are taken before and after each
drawing operation, so as to ascertain whether the metal is
being properly annealed or not. The blank also is tested
with a sclerescope before any work is done on it, and should
'strike 15. The head of the shell must strike between 40
and 50, being softer at the center than at the rim. The
readings are taken on four radii on the head, and at inter-
vals of Vs to 3/16 inch apart. In heading, considerable dif-
ficulty was at first experienced in securing the correct scle-
CARTRIDGE CASES 193
roscope readings. Instead of the head being harder at the
rim than at the center, the reverse was the case. It was
found that the metal in flowing towards the center packed
up to such an extent that the case was made considerably
harder at this point. A method which overcame this diffi-
culty consisted in drilling a %-inch hole down through the
primer pocket previous to the heading operation. This al-
lowed the metal to flow towards the center of the head with
comparatively little resistance, and hence the correct hard-
ness was obtained at the rim, as well as in the center of
the head. The machining of the head and mouth is accom-
plished in Bullard special cartridge case trimming machines
of the double-ended type, that is, one set of tools are located
in one end for machining the mouth and another set of tools
held in the turret and on the cross-slide for machining the
head and primer pocket. Following this, hand-reaming and
hand-tapping operations are accomplished so as to get the
desired accuracy and fit in the primer pocket. Inspecting
and stamping operations finish the principal operations on
the cartridge case.
CHAPTER VII
SPECIFICATIONS FOR THE MANUFACTURE AND
INSPECTION OF THE RUSSIAN
3-INCH SHRAPNEL SHELL
The following specifications relating to the 3-inch Russian
shrapnel shell are abstracted from the official specifications,
and contain all the essential points required to be known by
the manufacturer or the inspector of shrapnel shells. The
specifications deal in detail with what is known as the "test
consignment" of shells, the "proof consignment" of shells,
and the methods of inspecting.
Clause 1 . General Conditions. The shrapnel shell con-
sists of the following parts : steel body with copper driving
band, steel diaphragm, steel fuse tube, steel fuse base, brass
socket nut, bullets, two steel fixing screws, two steel threaded
plugs, and a zinc plug. The selection of the material to be
used for the shell and the parts is left to the discretion of
the manufacturer, but on the condition that it meets the
requirements given in the following specifications. Before
beginning the manufacture of an order, the manufacturer
must submit a test consignment of shells.
Clause 2. Test Consignment of Shells. The selection
of shells for the test consignment is left to the discretion of
the manufacturer. The trials of the test consignment are
carried out in the presence of the inspector appointed by
the government for which the shells are made, and of the
representative of the firm whose shells are tested. The
methods of manufacture of the test consignment of shells
must be known to the inspector and must be done in accord-
ance with the requirements in the following specifications.
All shells forming the test consignment must be similar in
material and made by the same methods of manufacture.
The submission of the test consignment is not required
for those firms who have already submitted one, and after
the completion of an order have received a new order for
the same shells, provided the mechanical conditions for
194
RUSSIAN SHRAPNEL SHELL 195
manufacturing the same have not been altered. Firms are
allowed to begin the manufacture of the shells before deliv-
ering the test consignment, but on the condition that in the
case of unsatisfactory results of the trials of the test con-
signment, all shells previously manufactured by the firm
must be rejected.
The test consignment consists of fifty shrapnels, out of
which twenty-five are tested, by firing, with a view to as-
certaining their accuracy and strength, twenty-two for
strength only, and three shrapnels are left for mechanical
tests by breaking the test pieces made from them in a test-
ing machine. In the case of the last three shells it is nec-
essary to ascertain before cutting the test pieces from them
that the driving bands are pressed on correctly, by remov-
ing them. In addition to this, the strength of the shrapnels
is tested by exploding them in a pit. For the pit test, those
shells are used which are found undamaged after being fired.
For this trial, ten shrapnels are used. Before firing the
test consignment of shrapnels and before the pit test, the
mechanical test must be carried out, and the two first men-
tioned tests may be carried out only if the metal shows re-
sults answering the conditions mentioned in Clause 3 of
these specifications.
The test consignment will be considered as passed if the
following results are obtained :
1. If during the mechanical tests the metal answers to
the conditions laid down.
2. If during firing no shell is broken in the gun or imme-
diately in front of the muzzle.
3. If during firing no socket is separated from the shell
in the gun or immediately in front of the muzzle.
4. If on cylindrical parts of the bodies of shrapnels re-
covered after firing no signs of the rifling are to be found.
The slight impression from rifling on the central portion of
the shell cannot, however, be taken as a reason for the re-
jection of the shell, provided that it is noticed only on one-
half of the circumference.
5. If shrapnels recovered after firing do not show any
dent in their bases or shearing of the socket, or if the in-
196
RUSSIAN SHRAPNEL SHELL
SMOKE COMPOSITION
ASSEMBLY lti8+".OlJ"
8.8 0.04- 4*iJ8-
SECTION THROUGH B-B /f
6 THREADS PER INCH 0-1875 DIA. TAPPED HOLE, 24 THREADS PER INC*
DIAPHRAGM STEEL
0.375 DIA. TAPPED HOLE,
16 THREADS PE
FOR FILLING SHELL WITH RESIN
AND TO BE AFTERWARDS PLUGGED
5.5695
CENTRAL TUBE STEEL
24 THREADS PER INCH
j< 0.3r H
NG SCREW FOR FUSt SOCKET STEEL
2 REQUIRED
FIXING SCREW FOR FUSE STEEL
1REOU.REO,
DRIVING BAND COPPER
SCREWED PLUG STEE
Fig. 1. Russian 3-Inch Shrapnel Shell and Component Parts
RUSSIAN SHRAPNEL SHELL 197
crease in the diameter of the cylindrical part of the body
does not exceed 0.010 inch.
6. If shrapnels recovered after the firing do not show in
more than 15 per cent of the cases the protrusion of the
upper end of the central tube from the countersink of the
brass socket nut. All these shrapnels must be dismantled
for the inspection of the central tubes; the central tubes
must not show any considerable sign of buckling, cracks or
protrusion into the powder chamber.
7. (a) If during pit test, shrapnels do not show any
breaking away of the bases, if their bodies be found intact,
and if the same results be found on the shrapnels picked
up after firing.
(b) If out of ten shrapnels tested in the pit not more
than three show broken bodies.
8. If shrapnels do not show the separation of driving
bands from the shell, nor displacement of same, if loosely
fixed, and the accuracy of the firing in a vertical plane be
not below the requirements given in Clause 19. The signs
of the rifling on the driving bands of the recovered shells
should be correct and not enlarged.
If the results of the trial of the test consignment give
unsatisfactory results with reference to any of the above
seven first conditions, or to all of them, the firm will be al-
lowed to submit a second test consignment. In the case of
unsatisfactory results of the test consignment with reference
to the eighth condition, the firm has the right to submit
additionally twenty-five shrapnels for accuracy firing trials
only, but these shrapnels must also answer to the other seven
conditions. If the trials of the test consignment show satis-
factory results, the firm may proceed with the manufacture
of shrapnels, but under the condition that the material and
method of manufacture will be similar to those used for the
manufacture of the test consignment.
In the case of unsatisfactory results of the test of the
second test consignment, the contracting government has
the right to cancel the order with the firm for delivery of
the shrapnels in question. All the test consignments of
shrapnels must be at the contracting firm's expense.
198 RUSSIAN SHRAPNEL SHELL
Clause 3. Breaking Tests of the Material used for Bodies.
These tests must be carried out at the works where shrap-
nels are manufactured. Three flat test pieces must be cut
from the cylindrical portion of the body parallel to its axis
and immediately above the driving band. The dimensions
of test pieces are as follows : Width, 0.750 inch ; thickness,
0.150 inch; distance between marks, 2 inches. The outline
and dimension of the ends must suit the holders of the
testing machine. The metal of the bodies will be consid-
ered satisfactory if it shows a breaking strength of 82.7
kilograms per square millimeter (52.5 tons per square inch)
with a final elongation of not less than 8 per cent. In addi-
tion to this, the inspector must select two bodies from the
test consignment before the beginning of final machining
for cutting from the round test pieces with a diameter of 0.3
inch, length 2 inches between marks, three test pieces being
cut from each shell. The breaking test of these test pieces
must be carried out on the testing machine, and the elastic
limit of the material must be ascertained on them.
Clause 4. The Proof Consignment of Shrapnels. As
mentioned, the shrapnels under order must be manufactured
from similar material and by similar methods to the shrap-
nels of the test consignment. The acceptance of shrapnels
for the service, however, can be effected only after "proof
tests" of the mechanical qualities of the metal used, of the
accuracy of firing, and of the strength and proper assem-
bling, and pit tests.
The whole order is sub-divided into consignments of 5000
shrapnels each. The method of manufacture of the shrap-
nels must be entirely the same for the whole consignment.
In the case of the order being placed for a number of
shrapnel less than 5000, the whole order will be treated as
one proof consignment ; in the case of the order being placed
for a larger number of shrapnels, the remainder from a full
proof consignment must be treated as a part of the previous
consignment, when it is less than half of the proof consign-
ment, and must form a separate proof consignment when
it is more than half of same.
RUSSIAN SHRAPNEL SHELL 199
The choice of shrapnels for proof must be made by the
inspector personally from the proof consignment submitted
by the firm. The choice must be made after final inspection
of the whole consignment. The works have the right to
challenge the shrapnels chosen by the inspector for the
proof, having the right to do it only twice. The shrapnels
challenged in that manner must be destroyed, so as to pre-
vent any further submission of same for proof. The shrap-
nels challenged must be replaced by the firm.
For the mechanical tests of the metal, it is recommended
to select bodies which were rejected on account of their
dimensions, but in the case of the absence of any bodies re-
jected for the dimensions, the works must provide good
bodies selected by the inspector. Not less than ten bodies
must be chosen from the proof consignment. The rules
and requirements for the metal used for the shrapnel bodies
were given in Clause 3.
In the case of satisfactory results of these mechanical
tests, the firm must submit from each proof consignment
fifty shrapnels for the firing trials for their strength. After
firing trials, the pit tests must be carried out, for which
proof recovered shrapnels which do not show any damage
after firing will be used. Ten shrapnels must be used for
pit tests.
All proof tests must be carried out in the presence of the
inspector sent for this purpose to the works, and the me-
chanical tests of the metal must be carried out by the in-
spector himself. The projectiles used for the proof firing
must not be painted but only covered with machine oil.
The consignment will be accepted if the mechanical or
firing proof tests fulfill the same requirements as have been
laid down in Clause 2, Conditions 1 to 8, with the excep-
tion that in Condition 6, in the case of the proof test, 20
per cent, instead of 15 per cent, as in the case of the con-
signment test, may show protrusion of the upper end of the
central tube from the countersink of the brass socket nut.
If, during firing, breakages of the shrapnels in the gun or
immediately in front of the muzzle should occur, the whole
consignment must be rejected.
200 RUSSIAN SHRAPNEL SHELL
In the case of unsatisfactory results with reference to
trials mentioned in Clause 2, Conditions 3, 4, 5, and 6
(which must not be more than one shell with reference to
Conditions 3, 4, and 5), the firm has the right to submit
100 additional shrapnels chosen by the inspector for the
firing for recovery proof. If during pit tests more than
three shrapnel bodies are broken, an additional five shrap-
nels must be subjected to the same test, but for the accept-
ance of the consignment it is required that, in total, no
more than five broken shrapnel bodies occur.
With reference to damaged or displaced driving bands,
or the impression of the rifling on them not being clear, or
being enlarged, it is left to the discretion of the contracting
government to demand the changing of the driving bands
on the whole consignment, after which rebanding they must
be submitted for second proof, twenty-five shrapnels being
tested for accuracy : these shrapnels must be chosen by the
inspector after reviewing the whole consignment. If dur-
ing the secondary firing trials which take place on account
of failures with reference to any one of the above-mentioned
reasons, further failures to the same effect take place, the
question of the acceptance of the whole consignment must
be referred to the respective military administration.
In the case of the failures of both trials, first and sec-
ondary, the permission for the further manufacture of pro-
jectiles by the firm in question will be left to the discretion
of the respective military authorities.
In the case of the acceptance of the consignment after the
proof, the shrapnels used for the proof in question, fifty
in number, must be taken from the order. Any other
shrapnels, used for proof in addition to the above-mentioned
number, must be at the expense of the manufacturer.
Clause 5. The Rights and Duties of the Government
Inspector. The inspector's duty consists not only in the
acceptance of the manufactured shrapnels, but also in look-
ing after the methods, etc., used in the manufacture. In
order to do this, the inspector must be given the right of
access to any work and test referring to the shrapnel
manufacture.
RUSSIAN SHRAPNEL SHELL 201
The inspector has the right to inform the manager of
the works of all defects noticed by him in manufacture of
the shrapnels, as well as of those which occur in the shrap-
nels submitted for acceptance, and he has the right to sug-
gest improvements to the manufacturer ; it is left to the dis-
cretion of the manager of the works to make use of these
suggestions, if it is found advisable, but the inspector has
not the right to interfere with the orders issued in the
works.
Before submitting to the inspector the shrapnels manu-
factured the works must pass them by their own examin-
ers ; these examiners must work to the instructions given to
them by the works, and prepared to the inspector's satis-
faction. The inspector has to gage shrapnels by the gages
stated in the following specifications. He also must check
them with reference to their dimensions, as given on the
drawings, before beginning inspection.
Clause 6. The Condition in which Shrapnel Bodies are
Submitted. Steel shrapnel bodies are submitted to the
first inspection without socket, driving band, and inner
parts. The outside cylindrical portion of the bodies as well
as the enlarged centering portion must be machined and fin-
ished ; shrapnel bodies must be submitted with grooves for
driving bands and with other grooves in the base of the shell.
The rounded portion of the bodies above the enlarged cen-
tering portion must be machined only preliminarily. The
inside of the bodies must be finish-machined, and the
shoulder for the diaphragm as well as the cylindrical por-
tion of the body against the diaphragm must be properly
finished ; the upper part of the inside surface must be pro-
vided with threads for socket. The remaining portion of
the inside surface might be roughly machined. The base
of the shrapnels may be left with a boss outside with cen-
ter marked on it, but the remaining portion of the base must
be finish-machined. This applies to the first inspection.
Clause 7. The First Inspection of Shrapnel Bodies.
The surface of the enlarged centering portion must be
perfectly smooth and the cylindrical portion of the bodies
must not show any tool-marks, except slight ones. The
202 RUSSIAN SHRAPNEL SHELL
outer surfaces of the central portion and the enlarged cen-
tering portion must be polished. Special care must be taken
in polishing the enlarged centering portion. The inside
surface of the bodies must be clean and smooth. The outer
and inner surfaces of shrapnels must not show any cracks,
fissures, or black lines (not even the very slightest of
these), nor burrs. The inner surface of the bodies may
show separate dents due to slag, but these dents must be
of a very slight nature. The thread in the upper end of the
bodies for the socket must have at least five full turns.
Clause 8. The Checking of the Weight of Shrapnel
Bodies. Out of each one hundred bodies submitted to the
inspector, at least ten bodies must be weighed. These
weights will assist the inspector with reference to the di-
mensions of the bodies, and might draw his attention to the
dimensions of those parts for measuring of which there
are no gages provided. In addition to this, during the
manufacture of the test consignment, the inspector must
ascertain the mean weight of the shrapnel bodies in this con-
signment, as well as any possible variation in any direction.
Clause 9. Inspection and Test of Copper for Driving
Bands. Pure copper is used for the driving bands. It
must be of the best quality, and hard drawn ; ordinary cop-
per, not drawn, must not be used for driving bands. The
copper strips must be cut into pieces of the lengths re-
quired for their placing on the shrapnels. The copper
strips must be submitted to the inspector for acceptance
and for the following tests:
1. The strips must be bent double in cold condition un-
til the ends meet; when the ends meet, the strip is ham-
mered until both halves are flat ; if during this test the strip
does not show any cracks or breakages, the metal will be
considered as accepted.
2. The strip is hammered in cold condition until its
thickness is reduced one-half; after this trial it must not
show any fissures or cracks.
Not more than 1 per cent of the strips submitted must
be subjected to the above tests-.
RUSSIAN SHRAPNEL SHELL 203
If it is found that any of the strips tested will not stand
the tests, the whole consignment of strips is rejected, or is
returned to the firm for reviewing, so as to give the firm
the possibility to submit again that part of the consignment
which might be considered good. During secondary test
another 1 per cent of strips will be chosen, and in the
case of any failures the whole consignment will be finally
rejected.
In case of satisfactory results in the tests mentioned,
the inspector examines the copper strips so as to ascertain
that they are of proper cross-section; special notice must
be taken with reference to fissures. Fissures exceeding one-
tenth of the strip in length are not allowed. The inspector
must examine 20 per cent of all strips, and, during this
examination, if even one strip be found with fissures longer
than mentioned, the whole consignment of strips will be re-
turned to the firm for reviewing. If during secondary ex-
amination the inspector finds even one fissure exceeding the
mentioned length, the whole consignment of copper will be
rejected.
Clause 10. Fixing of Driving Bands. To prevent cracks
in shrapnel bodies during the fixing of the driving bands,
a mandrel must be placed inside the bodies, and this man-
drel must fit the inside surface of the bodies tightly. The
inspection of the grooves must be carried out by means of
the gages made by the firm to suit the inspector's require-
ments. To facilitate the fixing of the driving bands on the
shrapnel bodies, the bottom of the grooves may be provided
with waved ribs. The depth of these grooves must not
exceed 0.005 inch. The width of the surface with the waved
ribs is left to the decision of the firm and inspector.
The method of fixing the driving bands is left to the
discretion of the firm, the only requirement being that the
order must be manufactured by the same methods as used
for the manufacture of test consignment, provided that the
firing trial of that consignment was satisfactory. The
number of shrapnels supplied by the firm for this firing and
for the inspection of the driving bands is mentioned in
Clause 2. If the firm is proposing to alter the method of
204 RUSSIAN SHRAPNEL SHELL
the fixing of the driving bands, it must submit, at its own
expense, a test consignment of 25 shrapnels for firing
trials.
During the manufacture of the order for shrapnels the
inspector has the right to choose, if he thinks it necessary,
from each consignment submitted to him, not more than
1 per cent of the projectiles for the removal of their driv-
ing bands, in order to ascertain how close they are to the
shrapnel bodies. The inspector also has the right to de-
mand an accuracy trial with some of the above-mentioned
shrapnel, but in this case he must give detailed reasons
for doing so. If the results of this firing are unsatisfac-
tory, the military authorities have the right to demand the
replacement of driving bands on the whole order.
Clause 11. Secondary Inspection of Shrapnel Bodies
after the Firing of Driving Bands. The shrapnels ane sub-
mitted for the secondary inspection with fixed driving
bands, finished sockets, steel diaphragms in place, central
tubes and socket nut, but without socket fixing screws, as
well as fuse fixing screws. The central bosses on the base
must be cut away in cases where the shrapnels were sub-
mitted with them for the first inspection. The powder
chamber, lower portion of steel diaphragms, and inner sur-
face of central tube must be covered with durable varnish.
During this inspection special care must be taken to
ascertain the proper fixing of the driving band. The proper
fixing of the driving bands is ascertained by (1) sounding
them with small hammers, and (2) removal of driving
bands from some shrapnels, preferably those rejected. The
driving bands when being sounded with hammer must not
make any jarring sound. The jarring sound is only al-
lowed at the joint of the driving band, for not more than
one-tenth of its length; the bands not answering to these
conditions must be replaced by new ones. The driving
bands, after being removed from the shrapnel, must have
impressions of the waved grooves on the bottom of the
groove; the inside surface must not show the pink color of
the unused copper, but must be smooth and give a slight
reflection.
RUSSIAN SHRAPNEL SHELL 205
When removing the driving band, special attention must
be paid to the fact that the bands fit properly into the
sides of the groove, and that they are close to the shrapnel
bodies. In the case of copper strips being too wide, the
shrapnel bodies show cracks, sometimes on account of the
method of fixing and sometimes on account of too high a
pressure. These cracks can be ascertained by sounding the
shrapnels with a hammer ; the cracked shrapnels will make
a dull sound. Such shrapnels must be rejected.
During secondary inspection, the inspector must ascer-
tain the following facts :
1. If the powder chamber, lower surface of steel dia-
phragms, and inner surface of the central tube are var-
nished ; if steel diaphragms fit properly in the corresponding
place of the shrapnel bodies ; steel diaphragms must bear on
the lower surface of the shoulder and must be in close con-
tact with the inside surface of the shrapnel bodies. Special
care must be taken with reference to the tight fitting of
the steel diaphragms.
2. The base of shrapnel bodies must be absolutely
smooth; attention must be paid to the presence of rough
surfaces; black spots, cracks, or any damages, which are
not allowed on the site of the central boss ; shrapnel bodies
with such defects are not allowed.
The final finishing of the driving band may be done after
the shrapnels are nickel-plated, at the discretion of the
inspector.
Clause 12. Inspection of Steel Diaphragms. Dia-
phragms are made from steel stampings under the hammer
or press. The metal, with reference to the mechanical
qualities, must meet the requirements set forth for the
shrapnel bodies (see Clause 3). The holes for the central
tubes must be drilled; these holes must be made with a
shoulder for the central tube ; the outer surface of the dia-
phragm, as well as the shoulder of the hole for the central
tube, must be accurately machined. The diaphragms must
not show any cracks or other defects.
The test of the metal for the diaphragms consists of ham-
mering them by the dropping of a weight from a certain
206 RUSSIAN SHRAPNEL SHELL
height. The number of blows which the diaphragms can
stand without any cracks must be ascertained by the in-
spector during the manufacture of the test consignment of
shrapnels. In addition to this, the quality of the metal
must be ascertained by the Brinell test. During firing, the
diaphragms must not show any dents; this fact must be
ascertained on some shrapnels recovered after the firing.
The manufacturer must supply the inspector with ten
diaphragms for the mechanical tests of material. These dia-
phragms will be chosen by the inspector from the total num-
ber of diaphragms for the whole consignment. For the
hammering tests, not more than one per cent of the total
diaphragms must be chosen, and the Brinell test must be
carried out on not less than one per cent of the whole num-
ber of diaphragms. In the case of satisfactory results, the
whole consignment is accepted; otherwise, additional tests
on two per cent of the diaphragms must be carried out, and
in the case of unsatisfactory results, even on one diaphragm,
the whole consignment will be rejected. Diaphragms must
be submitted for inspection in quantities not less than 200.
The lower surface of the diaphragm must be varnished after
inspection.
In the case of the manufacturer being allowed to make
shrapnels without submission to test consignment, as per
Clause 3, the inspector must test the diaphragms as usual.
Clause 13. Inspection of Central Tube. The central
tubes must be made of steel, must not show any cracks,
must be properly welded, and must be of similar thickness
on the whole length. For the purpose of ascertaining the
mechanical qualities of the metal used for the central tubes,
small cylinders % inch in length (li/ 2 times the diameter
of the tube) must be cut from some of the tubes which
have been previously properly measured; these cylinders
must be subjected to a compression test under the press.
The minimum resistance shown by these cylinders under
compression, before the beginning of buckling, must be not
less than 14.45 tons per square inch. The outer as well as
the inner surfaces of tubes must be smooth and their ends
must be cut perpendicular to their axes. The length of the
RUSSIAN SHRAPNEL SHELL 207
tube is ascertained during the assembling of the shrapnel.
In the assembled shrapnel, the upper end of the central
tube must be inside of the countersunk hole provided for in
the socket nut.
Clause 14. Inspection of Sockets. Sockets must be
manufactured from steel. The breaking strength of steel
used for sockets must be of about 60 kilograms per square
millimeter (38.1 tons per square inch), with an elongation
not less than 16 per cent (the distance between marks be-
ing 2 inches). Sockets are submitted for inspection in
quantities of not less than 100; they must be tapped with
thread on the inside as well as on the outside surfaces;
the conical portion of the surface must be machined; the
upper surface must be machined, but this machining may
be left rough at this stage; those parts of the sockets by
which they are fixed to the shrapnel bodies must be accu-
rately machined; the sockets must be accurately cut. The
sockets must be provided with two holes, one for filling with
resin, and another one for the escape of gases. If sockets
are stamped, the outer surface of the stem can be left
without machining, but it must be very smooth. The upper
surface of the sockets may be submitted to the inspector
without being finish-machined. The sockets must not
show any signs of cracks, fissures or any rough surface.
Chipping in the thread of the hole or on the conical fuse
seat may be allowed, but of a very slight nature.
To ascertain the mechanical qualities of the metal used
for sockets, the inspector has the right to carry out the
tests on one per cent of the sockets from each consignment.
For this purpose, rings must be cut from the upper portion
of the sockets, and these rings are subjected to the ham-
mering test by a weight dropped from a certain height.
In addition, the sockets must be tested with the Brinell
test, and for this purpose not less than 1 per cent of the
sockets must be used.
Clause 15. Inspection of Brass Socket Nuts. The
socket nuts must be cast of an alloy consisting of 2 parts
of copper and 1 part of zinc, taken by weight. The socket
nuts are submitted to the inspector after being finally ma-
208 RUSSIAN SHRAPNEL SHELL
chined, threaded, with finished upper and lower surfaces,
with central hole made to the drawing, and with slot for the
key. Socket nuts must not show any defects.
Clause 16. Bullets and Smoke Compositions. Bullets
must be of a true spherical shape; they must be cast of an
alloy consisting of 4 parts of lead and 1 part of antimony,
taken by weight ; sprues must be cut off, and the surface of
the bullets must be smooth. The diameter of the bullets
is 0.5 inch; mean weight, 0.376 ounce. Separate bullets
may differ from the mean weight, but they must not be less
than 0.373 ounce, and not more than 0.381 ounce. Under
slight hammering the bullets must not show any cracks.
The force of the blow must be decided by the inspector, the
reason for this test being to ascertain if the bullets can be
used in shrapnels where they are slightly compressed, as
after this pressure they must not show any cracks. Shrap-
nel must contain from about 256 to 265 bullets.
The bullets must be placed in proper layers, and each
layer must be slightly pressed in, but after this .pressure
bullets must not be deformed to any noticeable extent, ex-
cept those in the bottom layer. Layers consist of 17 or 18
bullets, except the top layers, which have about 20 bullets
each. The five bottom layers of bullets must be covered
with smoke composition made of metallic antimony and
magnesium in the following proportions, by weight : 55 parts
of antimony and 45 parts of magnesium; 0.75 ounce of
smoke composition must be put in each shrapnel. This
composition must be put in after the first five layers of bul-
lets are in place, and the shrapnel must be shaken in order
to settle the powder. The smoke composition must ignite
very quickly. The inspector must see that the composition
is made from the magnesium and antimony as stated above.
With bullets in place, and with socket in proper position, the
shell must be filled with melted resin.
Clause 17. The Third Inspection of Shrapnels and
Checking of Their Weight. The shrapnels for the third
inspection are submitted after being fully assembled and
charged with the bullets and smoke composition, and after
being filled with resin; the holes in the sockets used for
RUSSIAN SHRAPNEL SHELL 209
filling with resin and for the escape of gases must be stop-
ped with threaded steel plugs. These plugs must be riveted
over and polished flush with the surface of the socket.
During the third inspection, the shrapnel is gaged with
special gages to check shape ; the hole for the fuse is tested
by a special screw gage; copper driving bands must be in-
spected and gaged. After this inspection the shrapnels
are weighed. The shells which show the ends of the driv-
ing bands not completely touching each other, may be ac-
cepted if the distance between them is very small.
The outer surface of the socket must be finish-machined
and must be smooth and perpendicular to the center line of
the fuse socket. The socket must be fixed by means of
steel screws, the outer ends of which must be cut flush
with the surface of the shrapnel, and polished over.
During this inspection, the inspector must ascertain that
the head portion of the shrapnels does not show any cracks
due to the drilling and tapping of the holes for the screws.
The head of the shrapnel must be provided with a tapped
hole for the fuse securing screw. The head of this screw
must be flush with the shrapnel bodies. The upper end of
the central tube must fill completely the countersunk part
provided for it in the socket nut, if it is in proper position.
The steel gage rod dropped into the opening of the central
tube must reach the base of the shrapnel.
To ascertain the proper assembling of the inner part of
the shrapnels, the inspector has the right to demand dis-
mantling of not more than 0.5 per cent of the shrapnels
submitted. While inspecting the dismantled shrapnels, the
inspector must ascertain the following points :
1. If the thread of fixing screws for socket and fuse, as
well as the threads in holes for them, are cleanly cut, and
if the length of these screws is sufficient.
2. If the socket remains steady when screwed into the
shrapnel bodies, before being fixed with screws.
3. If the end of the central tube remains clean and the
central tube itself is not damaged by the bullets.
4. If the bullets are covered with resin and if the shrap-
nels are filled with smoke composition.
210 RUSSIAN SHRAPNEL SHELL
5. If the number of bullets is correct, and also that they
are not appreciably damaged after pressing.
6. If the steel diaphragm is in the right position in the
shrapnel.
After the third inspection the shrapnels must be weighed ;
the normal weight of the assembled shrapnels, without zinc
plugs, must be 13 pounds 7.33 ounces 1.053 ounce. All
shrapnels passed by the inspector must be stamped on the
base.
Clause 18. Nickel-plating, Varnishing and Oiling. All
the outside surfaces of the shrapnel with the exception of
the copper driving bands must be nickel-plated and var-
nished. This nickel-plating and varnishing must be dura-
ble. The manufacturer must take steps to prevent the
passage of the liquid inside of the shrapnels during nickel-
plating. The shrapnels must be inspected by the manu-
facturer after being nickel-plated so as to ascertain that
no liquid passed inside the powder chamber, and, if nec-
essary, the chamber must be cleaned. The shrapnels must
be submitted for final inspection after being nickel-plated
and varnished.
The socket in the front portion of the shrapnel must be
oiled and covered with the zinc plug shown in Fig. 1; the
socket must be fitted with fixing screws for the fuse; the
screws must be oiled with naphtha grease. The copper driv-
ing bands must be gaged during this inspection. While in-
specting the shrapnels, the inspector must see to the follow-
ing points:
1. That the driving bands are not damaged; shrapnels
with damaged bands must be returned to the works for new
bands.
2. That the nickel-plating of the shrapnels is sound and
that the nickel-plated surfaces do not show any signs of
rust.
3. That the fixing screw for the fuse is properly cut ; the
top of this screw, when screwed completely down, must
slightly protrude over the surface of the shrapnel. The
threads must be Whitworth, 24 threads per inch. A plug
and ring gage must be provided for gaging this thread.
RUSSIAN SHRAPNEL SHELL 211
4. That the socket is free from rust.
5. That the powder chamber, as well as the inside of the
central tube, is clean.
The zinc plug must fit properly to the upper surface of
the fuse socket. The copper driving bands must be oiled
with naphtha grease to prevent them from corroding. The
shrapnel, before shipping from the works, must be packed
in strong wooden boxes. The details of the packing is left
to the discretion of the manufacturer, provided that it is
approved by the inspector. While packing, care must be
taken to place driving bands in guards to prevent their be-
ing damaged by knocks from the outside, or from rattling
one against the other, or against the packing during trans-
port.
The number of shrapnels packed in one box must not
exceed, in weight (box included), 253 pounds.
When shipping the manufactured shrapnels from the
works, two spare fuse fixing screws must be put in every
box. Spare zinc plugs, 5 per cent of the total number sup-
plied, must be delivered together with order and packed in
separate wooden boxes, 50 in each box.
Clause 19. Firing Tests. The works must deliver the
required number of shrapnels to the place where they will
be. tested. The proof by firing will be carried out with a
3-inch quick-firing gun with a charge of smokeless powder,
and with chamber pressure of 2400 atmospheres (15.75
tons per square inch).
The recovery proof must be carried out without bursting
charge, but the shrapnels must be fitted with time fuses.
When time fuses are not available, the proof must be car-
ried out with steel or brass dummy fuses similar to those
used for accuracy trials. These dummy fuses must be sup-
plied at the expense of the firm. Every shrapnel must be
weighed and the weights taken down.
The time fuse must be set a distance of from 1400 to 1635
yards. It must be noticed whether or not the fuse ex-
plodes. To obtain the best conditions for observation,
the firing must take place with sight set up 10 divisions
higher than is required by the range. Up to one-third of
212 RUSSIAN SHRAPNEL SHELL
the shrapnels proved for recovery must be fired with burst-
ing charge, so as to ascertain that they are properly assem-
bled. The fuse socket in the last mentioned cases must be
plugged with dummy fuses.
The firing must be carried out at such a range as to enable
the recovery of the shrapnels for inspection and measur-
ing of same ; all shrapnels, before firing, must be measured
on their cylindrical portion and the accuracy of the base
must be ascertained, in order to facilitate notice being taken
with reference to the bulging of the bodies and bases of the
shrapnels. The diameters of the cylindrical portion must
be taken in sections two inches apart. Marks must be made
on the copper driving bands and on the cylindrical part of
the shrapnel bodies adjacent, to facilitate notice being taken
of the displacement of the driving band, if such takes
place.
For accuracy trials, shrapnels without time fuse must
be used, and special steel or brass dummy fuses must be
screwed in; the outline and weight of this dummy must
be similar to that of the fuse, and the weight of the shrapnel
with such dummy must be 14 pounds 5.33 ounces. These
dummy fuses must be made by the manufacturer at his ex-
pense. The accuracy trials must be carried out by aiming
the gun at a vertical target at a range of 2335 yards.
After the firing trial for recovery and for accuracy, the
maximum possible number of shrapnels must be recovered
and inspected, as to any marks from the rifling on the
shrapnel bodies, any dents or damages on bases or heads,
any displacement of the driving bands or any shrapnels with
broken off bases. To ascertain the accuracy of fitting of
the steel diaphragms, and the condition of the bullets, two
shrapnels .must be dismantled. In addition, all those shrap-
nels which have displaced central tubes must be dismantled.
The shrapnels must be measured on their diameter in order
to ascertain the deformations. A pit test must also be
carried out. The shrapnels must be fully loaded for the
pit test and must be fitted with ordinary zinc plugs screwed
into the fuse sockets.
CHAPTER VIII
SPECIFICATIONS FOR THE MANUFACTURE AND IN-
SPECTION OF THE COMBINATION FUSE FOR
RUSSIAN 3-INCH SHRAPNEL SHELLS
The following specifications contain all the essential in-
formation relating to the Russian aluminum 22-second com-
bination or double-acting fuse for shrapnel shells used in
3-inch quick-firing field and mountain guns, as given in
the official specifications. This chapter, therefore, contains
a complete description of every part used in the fuse, to-
gether with complete details relating to the manufacture,
inspection, and tests.
Component Parts of Fuse. The fuse consists of over
thirty separate parts, the names of each of which are speci-
fied in the table below, together with their weights.
FUSE PART Weight In Ounces.
Avoirdupois
Stem (with cloth) 3.7166
Chamber bushing with needle for percussion detonator
cap (without powder) 0.1971
Bushing with needle for time detonator cap 0.0331
Plug (brass) in the flange of the stem 0.0150
Upper time ring (complete with powder; for filling in
both upper and lower time ring 0.24075 ounce avoir-
dupois of powder (fuse) are required; for 1-000
fuses, the following quantities of fuse powder are
required: for pressing into the time rings, approxi-
mately 16.25 pounds avoirdupois; for powder pellets
in the vents of the lower time ring, approximately
3.912 ounces avoirdupois) with powder and parch-
ment 1.1586
Lower time ring (see note in parenthesis on upper time
ring) with powder, asbestos, pins, and tin disk 1.1496
Nut 3.6278
Two set-screws for nut 0.0361
Tightening ring (split) 0.5492
Time detonator (assembled) 0.2632
Time detonator parts:
Pellet 0.1429
Rod 0.1023
Spiral brass spring 0.0030
Cap 0.0150
Safety bushing for the time detonator (the bushing for
the time detonator for mountain guns weighs 0.0677
ounce avoirdupois) 0.1128
213
214 RUSSIAN COMBINATION FUSE
Percussion detonator (assembled) 0.4514
Percussion detonator parts:
Pellet 0.3671
Brass bushing 0.0451
Lead disk (washer on flange) 0.0226
Cap 0.0166
Safety arrangement for percussion detonator:
Brass safety stirrup with brass control spring 0.0481
Steel spiral spring 0.1655
Lock bushing for the safety stirrup for percussion de-
tonator 0.5597
Base plug with counter safety lug and brass disk 0.5718
Lead disk 0.1520
Powder for the chamber bushing and transmitting duct
of stem 0.0572
Mean weight of complete and ready-for-firing fuse for
3-inch field gun 12.8628
Mean weight of complete and ready-for-firing fuse for
3-inch mountain gun 12.8177
The weights of the additional parts not included in
above list are:
Tin protecting cover with tape 1.0533
Copper wire for removing the cover 0.1053
Shell grease for lubricating grooves of stem 0.0196
Design and Construction of Stem. The stem is to be
cast of aluminum (or an alloy of aluminum and copper)
and pressed. The top of the stem is to be turned on the
outside into three cylindrical shoulders, the upper one be-
ing threaded for receiving the nut; on the surface of the
two upper shoulders, parallel to the axis of the stem, three
guiding grooves are milled. The base of the stem top
serves as a turning axis for the lower time ring. The
interior of the top of the stem is to be bored out to form
three cylindrical chambers, the lower of which is threaded
to receive the brass bushing with the conical steel needle;
the latter is lacquered and inserted into the bushing from
the bottom, its head being riveted. To prevent the un-
screwing of the bushing, the latter is nipped in two places.
A vent is drilled through the wall at the top of the stem.
The upper face of the flange of the stem has a rim on its
circumference, and on a radius located in a vertical plane
with the vent of the stem top, a transmitting duct is drilled,
reaching from the lateral surface of the flange to the pow-
der chamber of the fuse ; the upper face of the flange com-
municates with this duct through an ignition hole pasted
RUSSIAN COMBINATION FUSE 215
onto the top with a muslin disk. The transmitting duct
(covered with a neutral varnish) is filled, in the assembled
fuse, with grain powder (for 100 fuses, about 3.84 pounds
avoirdupois of unpolished rifle powder is required) and
closed with a brass plug. On the lateral surface of the
flange two annular grooves are milled out, the lower of
which has four recesses for staking in the tin cover.
On the lower face of the flange (two marks shall be
placed on this face, one giving the last two digits of the
year of manufacture of the fuses, and the other the number
of the control consignment of the same year) , at the ends
of a diameter, two slanting cuts are milled for the wrench
which screws the fuse into the shrapnel. On the same
lateral surface a conical mark is cut, colored red, for the
setting of the graduations of the fuse; on the top face of
the flange a cloth washer is pasted, with a hole punched in
it over the ignition hole. The cloth is pasted with a special
thick varnish which is also used for pasting the twilled tape
to the cover. The varnish consists of white resin, shellac
and turpentine soluble in alcohol. Through the lateral sur-
face of the flange a hole is drilled, leading to the lower face
of the flange and intended for fastening the copper wire for
tearing off the cover.
The tail of the stem is shaped with a smooth cone on the
top and a threaded cylinder at the bottom; the interior of
the tail is to be bored out to form three cylindrical cham-
bers, the upper and lower of which are threaded to receive
the chamber and the base plugs, and the smooth, middle
one, is intended for the percussion arrangement.
The Chamber Bushing. The chamber bushing (brass)
has four holes in its bottom for transmitting the flame into
the interior of the shrapnel shell, and one central hole into
which the varnished steel needle is screwed from the top.
The lower face of the bottom of the bushing is recessed for
locating the compressed brass counter spring of the percus-
sion safety stirrup. The inside surface of the bushing is
covered with neutral varnish, and, before filling it with
powder, a muslin and wax paper disk are deposited at the
bottom. The powder in the bushing is compressed slightly,
216 RUSSIAN COMBINATION FUSE
to prevent its scattering in handling, before screwing the
bushings in their places. The screwed-in bushing is nipped
in two places and its wall is drilled through the transmitting
duct, before charging the latter, for exposing the powder
in the bushing.
The Time Rings. Both time rings are cast from an
aluminum-copper alloy (copper from 2!/ 2 to 3 per cent) and
stamped in a die; on the under side of each ring a groove
with an intervening bridge and semi-circular arch is formed
by first stamping it in a die and then milling it. The grooves
are coated on the inside with Ossovetski's neutral varnish,
and fuse powder pressed into them. The portions filled with
powder are then turned off and a thin, parchment washer
pasted on their under surface with a neutral varnish. The
parchment of each time ring is punctured over the trans-
mitting hole, to hasten the transmission of the flame in
grape-shot firing.
The upper time ring is turned on the inside to form two
cones connected by a circular section; the lower cone also
terminates into a circular section having three protruding
lugs fitting into the three slots of the stem top, thus allowing
the time ring to slide vertically only along the axis of the
fuse. On the upper side of the time ring an annular groove
is to be turned for the reception of a soaked leather washer.
From the lower cone of the time ring an oblique hole is to be
bored, near one end of the bridge (left end in looking at the
lower end of the time ring) communicating with the trans-
mitting hole drilled through the composition groove.
Through this oblique hole the composition is ignited from
the time detonator cap of the fuse, assisted by the powdei
preparation pasted by means of alcohol varnish on the side
wall of the hole next to the bridge. From the circular sec-
tion-connecting both cones of the time ring to the under side
of the same, four gas escape holes are provided, facilitating
the escape of the gases from the burning lower time com
position.
The lower time ring is turned on the inside, providing a
slight cylindrical shoulder fitting on the base of the stem
top and turning freely around same. At one end of the
RUSSIAN COMBINATION FUSE 217
intervening bridge (opposite the one in the upper ring) a
transmitting hole is drilled through the bottom of the com-
position groove of the time ring, transmitting the flame
from the upper to the lower composition. To insure the
ignition of the composition, a powder pellet with a central
hole is inserted into the transmitting hole. From this trans-
mitting hole, a gas escape hole, located on a radius of the
time ring is provided, which at its base has a bursting
charge of powder (varnished) pressed into it, plugged up
with asbestos, and covered with a foil ring pasted with
varnish. This hole facilitates the escape of gases from the
burning composition of the lower time ring. The asbestos
plug prevents the possibility of a premature ignition of the
lower composition from the upper one, and the powder
charge is intended for an immediate clearing of the plug-
ging at the gas escape hole soon after the ignition of the
lower composition through the transmitting hole. The lat-
eral surface of the lower time ring is provided with :
1. Four pairs of pins inserted into corresponding holes
for the setting of the fuse by hand.
2. Two holes for a wrench, if same should be required
for setting the fuses.
3. Graduation from 10 to 130.
4. Separate graduation marked with the digit "5."
5. One notch marked in red and one notch marked in
black with letters as directed by the contracting govern-
ment.
The upper side of the lower time ring is covered with a
cloth washer having an opening opposite the transmitting
hole.
The Brass Nut. From the outside, the nut presents a
rounded surface terminating into an umbrella. Inside the
nut a thread is cut for screwing onto the top of the stem ;
the threaded hole opens into an oval cylindrical cavity com-
municating with the outside atmosphere by means of four
openings in the neck of the umbrella. The edges of these
four openings are milled out on a side opposite to the direc-
tion of the rotation of the shell to facilitate the escape of
gases. At the bottom of the nut an arch-like annular recess
218 RUSSIAN COMBINATION FUSE
is milled out for the accumulation of gases from the burn-
ing compositions of the time rings, whence they escape into
the above-mentioned oval cylindrical cavity through four
inclined channels, and then out of the fuse through the open-
ings in the neck of the umbrella. The nut is provided with
two brass screws for securing it in place, after being
screwed home on the top of the stem.
Upper Percussion Arrangement. The upper percussion
arrangement consists of a brass time pellet and safety fer-
rule ; the time detonating cap is inserted into the pellet and
is held in place by means of a brass rod and brass spiral
spring wound on the head of the latter. The safety ferrule
is a hollow cylinder with a side slot, resting on the shoulder
between the upper and lower chambers of the stem top. In
its outside appearance the time pellet represents a cylin-
der of two different diameters connected with a conical
slope; with the latter, the pellet resting on the conical en-
largement of the ferrule. The lower cylindrical part of the
pellet slides into the inside of the ferrule, and the upper, to-
gether with the projecting part of the rod, is located above
the top of the stem in the cavity of the nut leaning with
its steel spring against the arch of the cavity. The rod is
kept firmly in place, being staked in on the circumference
of the joint in two places.
On the top of the stem, embracing the middle smooth
cylindrical portion, the brass conical tightening ring is put
on, fitting into the conical seat of the upper time ring. The
ring is provided with a pin, which is guided in its move-
ments by one of the three grooves in the top of the stem,
opposite the vent. In order not to cover up the vent in the
stem top, a longitudinal slot is cut in the ring opposite the
former; the eight other grooves on the outside of the ring
facilitate the tightening of the ring.
Lower Percussion Arrangement. The lower percussion
arrangement is located in the tail of the stem between the
chamber and the base bushing and consists of a percussion
pellet, lock bushing, brass safety stirrup with counter
spring, steel spiral spring, and lead washer. The brass per-
cussion pellet, turned all over, is provided with : 1. Bottom
RUSSIAN COMBINATION FUSE 219
shoulder resting on lead washer in base plug; the top of
this shoulder is turned off and the strips of the counter
safety catch hold onto it. 2. Cylindrical shoulder with
lower turn of steel spiral spring embracing same and guid-
ing the compression of the spring when the lock bushing
is settling down. 3. Lead washer with rectangular open-
ing, coated with varnish, and placed on the upper face of
the shoulder. 4. Parallel faces along which are placed
the leaves of the safety stirrup. On the upper part of the
two opposite faces of the percussion pellet transverse cuts
are milled out into which special tongues of the leaves of
the safety stirrup fit. The safety stirrup with the counter
spring soldered to it has four leaves, two of which (oppo-
site ones) are bent in the middle outwardly and two of
which are straight, with only a slight outward bend at
their ends; the latter leaves have tongues for fitting into
the cuts of the pellets, as shown in Fig. 4, Chapter I.
The lock bushing is a hollow brass cylinder, the outer
upper portion of which is rounded off and made wider than
the lower one; the interior is bored out cylindrically and
then widened into a cone, which catches the straight leaves
of the safety stirrup when the lock bushing is settling down,
thus preventing the latter from moving upwards. The
steel spiral spring in conjunction with the bent leaves of
the stirrup hold the lock bushing over the percussion pellet.
The percussion cap is kept in place by means of a brass
bushing which is staked in from below in two places.
Base Plug. The base plug, which is made of brass, has
an annular groove formed at the bottom near the wall,
which serves for fastening the counter safety lugs made of
two strips of copper. At one end, the lugs are inserted in
the groove (at the opposite ends of a diameter), and at
this place the metal is jammed; with their other ends the
lugs catch onto the shoulder of the bottom flange of the
percussion pellet, inserted in the base plug together with
the lead washer. The base plug has a flat bottom with a
central opening covered with a brass disk ; in order not to
leave any space between this disk and its seat, the former
is covered with varnish from below; two other holes at
220 RUSSIAN COMBINATION FUSE
the bottom of the bushing, not drilled through, serve for
the insertion of a wrench.
Testing Fuses and Their Component Parts. These tests
are carried out as follows :
1. The brass safety stirrups and bushings (time and
percussion) are divided into lots of 500 each. Five per cent
of each lot shall be tested for bending in a hydraulic testing
press. The resisting force of the percussion safety stir-
rups must be within the limits of 58.68 to 85.77 pounds
avoirdupois, that of the brass counter springs between 2.71
to 3.16 pounds avoirdupois, and that of the time safety
bushing between 72.23 to 99.31 pounds avoirdupois. (For
fuses for mountain artillery, from 40.63 to 54.17 pounds
avoirdupois.) All the time safety bushings shall also be
subjected on the same press to a compression test of 72.23
pounds (for fuses for mountain guns, 45.14 pounds avoir-
dupois), and only those which have stood this test are
finally considered suitable for the assembly of the fuses.
2. The steel spiral springs shall have no more than 2%
turns, and the upper and lower one must lie in a horizontal
plane and approach the nearest turn. In compressing the
springs to 0.33 inch, the springs must withstand a pressure
of from 20.76 to 47.08 pounds avoirdupois, and after remov-
ing the compressive load must resume the dimensions within
the given limits.
3. One-quarter per cent of the completely assembled
percussion arrangement must be tested for determining the
correctness of the locking of the lock bushing with the
safety stirrup, with the former in its settling down position.
4. The counter safety lugs with the base plugs are made
up into lots of 500 each; 5 per cent of each lot, with the
inserted percussion arrangement held in place by bending
the lugs on the shoulder of the lower flange, are tested
under load for unbending the catches of the counter safety
lugs. At a load of from 3.61 to 5.42 pounds avoirdupois,
the lugs must release the pellet. The percussion and time
safety bushings and stirrups should be numbered with the
number of the lot, in the order of their manufacture.
5. In order to secure easy turning of the lower time
RUSSIAN COMBINATION FUSE 221
ring by hand, in setting the fuse, the pressure on the nut
in screwing it home should be determined by readings of an
automatic control wrench and should be between 6.32 and
8.12 pounds avoirdupois.
6. .For testing the degree of uniformity of the fuses,
they are divided into lots of not more than 500 each. The
testing for the full burning time of the fuse is to take place
on a special apparatus and shall.be determined by a stop-
watch; the mean arithmetical difference from the mean
time of burning shall be determined from six tested fuses
and shall not exceed 0.13 second. If a greater difference is
obtained, nine more fuses shall be burned and the mean
difference determined from fifteen separate readings. If
the result is more than 0.13 second, ten more fuses shall be
burned and the mean difference determined from all the
twenty-five fuses. If a lot does not fulfill the required test,
all the time rings shall be rejected and the powder in same
burned out.
7. In order to determine whether all the component parts
of a fuse are properly assembled and kept firmly in place
without moving, each fuse is shaken by hand and weighed;
if the smallest weight of a fuse is not less than 12.862
ounces avoirdupois (for a mountain fuse, not less than 12.81
ounces avoirdupois) and no displacement of any of its com-
ponent parts ascertained, the fuse is set on "grape-shot"
and provided with a protective tin cover; otherwise the
fuse shall be taken apart to determine whether all the parts
are inserted in the fuse.
8. The percussion and time detonator caps shall be
tested for their sensitiveness to ignition by being thrown
from a height of two feet for the former, and 1.5 feet for
the latter, on the same apparatus as caps for other fuses.
For testing the percussion caps, the lower percussion ar-
rangement is set, i. e., the lock bushing is set until locked
with the percussion pellet by means of the leaves of the
safety stirrup, and then carefully thrust onto the needle of
the tail of the stem.
For testing the time detonator caps, the time pellet is
first inserted into the safety bushing; this is done in order
222 RUSSIAN COMBINATION FUSE
to increase the weight of the pellet, as its own weight is
too small and would necessitate a considerable lifting of
the rod of the testing apparatus. In order to conveniently
insert the time pellet within the safety bushing, the cham-
ber in the top of the stem (the middle one) is bored out,
and the percussion pellet is carefully thrust onto the needle.
In testing the percussion detonator caps, the tail of the
stem is screwed into the end sleeve of the rod of the testing
apparatus, and in testing the time detonator caps the top
of the stem is treated in the same manner; in the latter
test, the time rings are first put on the flange of the stem.
For testing the caps delivered to the works manufactur-
ing the fuses in hermetically sealed boxes (1500 percussion
and 2500 time detonator caps in each lot), i/ 2 Per cent of
the percussion caps and 1 per cent of the time caps are
selected for this purpose. The caps are regarded as satis-
factory if, in testing the percussion caps, there will not be
more than 1 per cent of cases missing fire or failing to
knock out the brass disk from the base plug ; in testing the
time caps the number of cases of non-ignition of the time
rings shall not exceed Va per cent. The ignited percussion
caps must burn the muslin and paper disks placed at the
bottom of the chamber bushing and ignite its powder.
9. Out of a control consignment of 25,000 fuses, 25 shall
be selected for shaking tests on a testing machine during
IVa hour (10 fuses will be shaken in a horizontal position
and 15 in a vertical), in order to determine the servicea-
bility of the fuses under the most unfavorable conditions
which can be encountered in transporting the shells.
Equipment of Fuses with Protective Covers. The tin cap
covering the fuse is pressed into both grooves on the lateral
surface of the flange of the stem ; opposite the holes in the
lower groove the cover is staked in ; for waterproofing the
fuse, the grooves should be filled with grease (consisting
of 58 Va parts of beeswax, 291/2 parts of naphtha grease, and
12 parts of white resin). To conveniently throw off the
cover, a copper wire, stranded of four separate thin wires
to preserve its flexibility, is inserted in the upper groove
before putting on the cover. One end of the wire is slip-
RUSSIAN COMBINATION FUSE 223
ped through the opening in the flange and fastened at the
bottom; the wire then runs around almost the whole cir-
cumference of the groove, is bent in a right angle in the
direction of the markings on the flange to the top of the
cover, where it is knotted and kept in place by a protruding
button pressed out of the cover. A piece of twilled tape is
fastened to the wire, which tape, in turn, is pasted to the
body of the cover.
Boxing of Fuses. Each fuse with cover, after being
examined and the varnish of the tape being found perfectly
dry, is carefully wrapped in wrapping paper; 15 fuses are
placed in a zinc box padded at the bottom with perfectly
dry felt, and the spaces between the fuses filled in with felt
or cloth cuttings. The fuses are covered with felt padding
and the cover is soldered to the box. A paper ticket, pasted
on the top of the box, should contain the following infor-
mation : The number of the box in the order of manufac-
ture of the fuses in the current year, the year of their
manufacture, the name of the fuses and the quantity per
box, the number of the control consignment and of the daily
output, the time of pressing in the composition, and the
time of the ignition test. The dimensions of the box are:
length, 12.15 to 12.20 inches, width, 7.25 to 7.30 inches, and
height, 3.11 to 3.16 inches. Four zinc boxes are put into a
wooden box.
The following information should be given on the tag
pasted on the lower side of the wooden box cover: The
number of the box in the order of their manufacture in the
current year, the year of the manufacture of the fuses, the
kind of fuses, and the quantity in the box. On the top of
the box a stenciled inscription should be made giving the
number of the box, the quantity and kind of fuses, and the
year of their manufacture. On the side of the box the
number of the control consignment and the year of manu-
facture should be marked. On boxes containing fuses with
alloy time rings, the number of the box and the year of
manufacture on the cover of the box, as well as the number
of the lot and the year of manufacture on the side of the
box, should be colored red. The weight of one zinc box con-
224 RUSSIAN COMBINATION FUSE
taining fifteen fuses should be approximately 16.7 pounds
avoirdupois, and the weight of one wooden box containing
four zinc boxes be approximately 90.3 pounds avoirdupois.
Instructions for Conducting Firing Tests. The follow-
ing instructions for conducting firing tests are given in the
official specifications:
1. For firing tests, fifty-five fuses should be tested out
of a lot of 25,000 fuses or less.
2. The fuses are to be subjected to the following firing
tests, using cast-iron experimental shells : Field fuses will
be fired from a 3-inch quick-firing field gun at a muzzle
velocity of 1930 feet per second and mean pressure of not
more than 2400 atmospheres (35,500 pounds per square
inch), and a maximum pressure of not more than 2550
atmospheres (37,500 pounds per square inch) . Fuses from
a 3-inch quick-firing mountain gun, model 1904, are fired at
a muzzle velocity of 950 feet per second and a mean pressure
of about 1250 atmospheres (18,400 pounds per square inch) ,
or from a 3-inch quick-firing gun, model 1909, at a muzzle
velocity of 1250 feet per second and mean pressure of ap-
proximately 1700 atmospheres (25,000 pounds per square
inch).
(a) 25 fuses should be tested by firing for percussion
action at a distance of about 4900 feet.
(b) 25 fuses should be tested for firing for time action
by setting the fuse at 52 (mountain guns at 66) , or at any
other graduation depending on the atmospheric conditions
of the day, in order to obtain a mean bursting distance of
7000 feet, whereby the mean height of the bursting should
amount to approximately 0.012 of the distance.
(c) 5 fuses should be tested for "grape shot" action
without removing the protecting cover.
(d) Mountain fuses are also tested with 25 shots for
time action from a counter-storming gun at a distance of
3500 feet and a mean pressure of approximately 1100 atmos-
pheres (16,200 pounds per square inch).
3. A lot of fuses is considered satisfactory if:
(a) In firing for percussion action not more than 2 fail-
ures shall take place, whereby the bursting on ricocheting at
RUSSIAN COMBINATION FUSE 225
the second or further falls is considered as a failure.
(b) In firing with the fuse set at 52 or at any other
graduation, depending on the atmospheric conditions of the
day, in order to obtain a mean exploding distance of 7000
feet, not more than one failure shall result, and the probable
deflection determined from not less than 20 shots will not
exceed 84 feet. In case no failures should occur, it is
permissible in figuring the probable deflection not to take
into consideration one of the shots deflected not more than
420 feet from the mean point of explosion on the smaller
side, or one deflected on the larger side.
(c) In firing "grape shot," the. mean point of explosion
shall not be farther than 42 feet, and any individual explo-
sion not farther than 140 feet.
(d) In firing for time and percussion action not a single
premature explosion shall take place.
4. A lot which did not satisfy these conditions is ac-
cepted for a second test, if at the first test the following
conditions prevailed :
(a) Not more than 3 failures were obtained in firing for
percussion action.
(b) In firing for time action not more than two failures
took place, and the probable deflection did not exceed 98
feet.
(c) In testing for "grape shot" action not more than one
failure took place, the mean point of bursting being not
farther than 56 feet and any individual explosion not more
than 175 feet.
(d) In firing for time and percussion action not a single
premature explosion took place.
5. A lot which failed in the first test, but which satis-
fied the requirements of Paragraph 4 shall be tested over
again, according to Paragraph 3, on that point only in
which the lot failed in testing.
6. In order to be accepted for service, a lot must, at the
second test, give such results that the percentage of fail-
ures on time and percussion action obtained at the first
and second firing shall not exceed in its entirety the per-
centage which was determined in Paragraph 3 for corre-
226
RUSSIAN COMBINATION FUSE
spending tests. The probable deflections and mean dis-
tances of explosion obtained at the second test for time
action, and in testing for ' 'grape shot" action must satisfy
respectively the requirements as laid down in Paragraph 3.
7. A lot which did not satisfy both tests will not be sub-
jected to any more tests, and any further action will depend
upon the military authorities.
Machinery
Fig. 1. Russian Combination Time and Percussion Fuse
(Vickers Type)
Action of Fuses at Firing. In setting the fuses it is
necessary to bear in mind that each of the 130 graduations
of the fuse corresponds to approximately 140 feet (in fuses
for mountain artillery of the Russian 1904 model to 104
feet) in the change of the firing distance, the same as the
graduations on the sight of the gun. In firing, the time
pellet passes through the safety bushing, expanding the lat-
ter, and falling with the cap on the needle. The detonator
RUSSIAN COMBINATION FUSE
227
cap ignites the composition of the copper time ring through
the vent in stem top and the hole in upper time ring.
When the fuse is set on "percussion", the transmitting
opening of the lower time ring and the ignition of the
flange of the stem are located opposite the intervening
bridges, and the burning of the upper time composition is
not transmitted into the chamber of the fuse. In such a
case the shrapnel continues its movement until striking an
,H 0.183 L 0.170,
H 0.866 L 0.858 f7-r--f| u T
HDS. PER INCH R. H.
H O.SJ16 L 0.512
B 0.146 L0.13
OAH >JH4 =$'
U0.14L0.134
2JTHDS. PER INCH R. H'
^T^ T^DS. PER INCH R. H.
BODY ALUMINUM
HOLES DIA. X 0.05 DEEP
2.36 L2.34
Machinery
Fig. 2. Body of Russian Combination Time and Percussion Fuse
(Vickers Type)
obstacle. At this instant the lower percussion arrangement,
releasing itself from the grip of the lugs of the counter
safety catch and compressing the counter safety spring,
approaches the needle, which punctures the detonating cap ;
the flame from the latter together with the flame from the
powder of the chamber bushing are transmitted to the
bursting charge in the shrapnel shell. When the fuse is
set for "grape shot," the transmitting openings in the time
rings and the ignition openings in the flange of the stem
228
RUSSIAN COMBINATION FUSE
are brought so close to one another that the bursting of
the shrapnel must take place on the average not farther
than 42 feet in front of the muzzle of the gun.
Russian Combination Time and Percussion Fuse Vickers
Type. Since the outbreak of the present war, various
fuses have been used on Russian shrapnel shells. One of
the principal of these fuses is the Vickers type of combi-
nation time and percussion fuse shown assembled in Fig. 1,
and in detail in Figs. 2, 3, 4, and 5. While the original
Russian fuse shown in Fig. 4, Chapter I, and described in
the preceding pages, has, up to the present war, been the
only fuse used in this shell, it has largely been replaced by
^ a H0.20
TOP RING ALUMINUM
0.1 02 0.035
.152
BOTTOM RING ALUMINUM
Machinery
Fig. 3.
Top and Bottom Time Rings on Russian Combination Time
and Percussion Fuse (Vickers Type)
other fuses, because of the difficulties experienced in manu-
facturing it. The Vickers type of fuse is somewhat easier
to manufacture and, therefore, has been used to some extent
on Russian shrapnel shells. Another fuse that is now be-
ing adapted to the Russian shrapnel shell is the American
combination time and percussion fuse, Fig. 3, Chapter I,
which is also of the same type as the British fuse described
in Chapter XI. The chief difference in design between the
, ,. I1.4L1.39
122L0.12-*) \^ I* -H 1.618 1
24THDS.PERINCHR.H. __ 14 THDS.PER I NCH R.H. CAP.
TABLET BOTTOM RING, TABLET TOP RIN
INTERPOSED BETWEEN VEGETABLE PAPER VEGETABLE PAPER
CAP AND LINEN
WASHER BODY
CLOTH
THICKNESS H 0.045
L 0.035
WASHER, BOTTOM RING,
VEGETABLE PAPeR
WASHER, BOTTOM RING,
CLOTH
THICKNESS H 0.0*5
L 0.035
DISK. ESCAPE HOLE.
TABLET, FLASH HOLE vFf-ETArn e PAPER
IN TOP RING, 2 PER FUSE DISK ' ESCAPE HOLE .
SILK PAPER ALUMINUM
2 PER FUSE
STIRRUP SPRING,
TIME
RD-ROLLED SHEET BRASS
Fig. 4. Details of Russian Combination Fuse (Vickers Type)
229
230
RUSSIAN COMBINATION FUSE
WIRE 0.04 DIA. (APPROX.)
4 STRANDS 0.018 DIA.
END OF WIRE SECURED IN
FLANGE OF FUSE BODY
LENGTH OF WIRE-ABOUT 15..5
A -H 0.575 L 0.567 5\
FERRULE BRASS
STRIP SECURING WIRE
COTTON TAPE CEMENTED
TO COVER
DISK, SCREW
PLUG
PERCUSSION DISK i TIME
PELLET, DETONATOR,
PAPER CARD-BOARD
Machinery
Fig. 5.
Details of Russian Combination Time and Percussion Fuse
(Vickers Type)
standard Russian and the Vickers type of combination time
and percussion fuse is in the percussion and concussion ar-
rangements. It will be noticed in Figs. 1 to 5, inclusive, that
the details of the Vickers fuse are much simpler to manu-
facture. There is also an absence of the numerous springs
in the original Russian fuse.
CHAPTER IX
SPECIFICATIONS FOR THE MANUFACTURE AND IN-
SPECTION OF RUSSIAN 3-INCH SHRAPNEL AND
HIGH-EXPLOSIVE CARTRIDGE CASES
The following specifications are abstracted from the offi-
cial specifications for the Russian brass cartridge cases for
3-inch shrapnel and high-explosive shells, and contain all
the essential information relating to the requirements in
the manufacture and inspection of these cartridge cases.
Clause 1 . The Rights and Duties of the Inspector. The
inspector's duty consists not only in acceptance of the cart-
ridge cases manufactured, but also in looking after the
methods used in the manufacture of the cartridge cases,
and the brass used for them. In order to do this, the in-
spector must have the right of access to any work and tests
referring to the cartridge cases ; he must have the right to
enter any shop during any time of the day or night, where
the manufacture of the cartridge cases ordered may take
place, i. e., the casting and rolling of the brass, drawing,
annealing, finishing, etc.
If the firm with whom the order for the cartridge cases
is placed does not cast brass, but obtains it from other
works, the inspector has the right to visit these latter works
in order to ascertain the quality of the casting (and quali-
ties of copper and zinc) , method of cutting the top and bot-
tom parts of castings, method of rolling, etc. The inspector's
expenses with reference to his journey to the brass works
in such case must be borne by the firm with which the order
for the cartridge cases has been placed. The minimum
number of the necessary journeys must be determined be-
fore the placing of the order.
The firm, which is manufacturing the cartridge cases,
must have a testing machine for the mechanical tests of the
metal used for the cartridge cases; it must also possess a
microphotographical laboratory for the brass (the power
of the microscope must be at least 100). The firm must
231
232 RUSSIAN CARTRIDGE CASE
furnish the inspector with the results of all the chemical,
microscopical, thermal, mechanical and any other tests car-
ried out on the brass used for the manufacture of cartridge
cases, as well as on cartridge cases themselves. In addi-
tion to this, the inspector must be given the right to use all
the firm's testing plant for the above-mentioned tests. The
inspector must carry out the specified tests mentioned in
the following for the acceptance of the cartridge cases.
Independently of the above, if the inspector thinks it
necessary, for the purpose of ascertaining the qualities and
evenness of the material used for the cartridge cases, as
well as the cartridge cases themselves, to carry out in addi-
WEIGHT OF CASE WITHOUT PRIMER
NCES DRAM
2 9
H. 12.776" L. 12.736-
H.15.168"L. 15.148
Machinery 1
Russian 3-inch Cartridge Case
tion some other trials, the firm must provide him with all
necessary assistance.
The firm must place at the sole disposal of the inspector
sufficiently large dry and heated accommodations for carry-
ing out his inspection, provided with cupboards for his
gages; scales must also be provided; the place must be
lighted by electricity, and all necessary power for the in-
spection must be provided ; gages ; and a microscope of from
40 to 50 power.
All gages used for the gaging of cartridge cases must be
checked by the inspector before the beginning of the in-
spection, as well as during the inspection. Before submit-
ting the cartridge cases manufactured to the inspector, the
RUSSIAN CARTRIDGE CASE 233
works must submit them to their own examiners. These
examiners must work according to the rules given them by
the works, and prepared in conjunction with the inspector.
The firm must provide their examiners with a separate set
of gages manufactured similarly to those supplied to the
inspector.
The inspector has the right to inform the management
of the works of all defects noticed by him in the manufac-
ture of the cartridge cases, as well as of those defects which
occur in the cartridge cases submitted for acceptance. Fi-
nally, he has the right to suggest some improvements in the
manufacture of the cartridge cases ; it is left to the discre-
tion of the management of the works to make use of the
above suggestions, if it is found advisable by them to do so,
but the inspector has no right whatever to interfere with
the orders issued by the management of the works.
Clause 2. Test Consignment. Before beginning the
manufacture of the order, the works must submit a test
consignment. The cartridge cases for test consignment
must be manufactured to the approved drawings, and made
of brass according to these specifications. During the manu-
facture of the cartridge cases, it is required:
1. That the annealing of the cartridge cases shall be
regulated to prevent any over-heating of the metal.
2. That after the cartridge case is properly formed,
the upper half of the case shall be definitely annealed at a
temperature not less than 400 degrees C.
3. That the mechanical quality of the metal in the manu-
factured cartridge case shall be in accordance with these
specifications. The method of manufacturing the cartridge
cases, as well as the regulation of the annealing before
drawing, is left to the discretion of the works. The test
consignment must be inspected and gaged by the inspector,
and then sent for firing tests. The inspector must measure,
on all cartridge cases in the test consignment, the diameter
of the case near the bottom next to the flange, at a distance
of !/2 an d l*/2 inch from the flange.
After firing the first round, all cartridge cases must be
inspected and measured on the same diameters on which
234 RUSSIAN CARTRIDGE CASE
they were measured before firing. The cartridge cases
showing the maximum increase of diameter are to be re-
sized after each round, together with those that are doubt-
ful with regard to strength, if such re-sizing is allowed
by these specifications. The cartridge cases spoiled during
re-sizing must be replaced by new ones from the same con-
signment, but these new cases must be fired the same num-
ber of rounds as the old spoilt cases.
The consignment will be accepted:
1. If all cartridge cases after firing are extracted with-
out any difficulty.
2. If no case shows longitudinal or transverse cracks
(or any other cracks).
The cartridge cases which are supplied together with shell
must be checked and examined in order to ascertain whether
the shells are sufficiently secured in the case.
The test consignment of cartridges must be manufac-
tured at the expense of the works, but the tests are carried
out at the expense of the government.
In the case of an unsatisfactory test of the first consign-
ment, the works have the right to submit a second test
consignment. In the case of unsatisfactory results of the
tests of the second consignment, the military administra-
tion has the right to cancel the contract.
The inspector has to weigh all cartridge cases of the test
consignment, ascertaining thus the mean weight. In addi-
tion, the inspector must carry out the following test on the
cartridge cases of the test consignment:
1. Chemical composition of brass.
2. Mechanical and microphotographical qualities of
metal in the manufactured cartridge cases.
3. The temperature of the last annealing, i. e., the tem-
perature of annealing before last drawing, temperature be-
fore compressing, and temperature of the final annealing
of the finished cartridge case.
The temperatures of annealing must be ascertained by
pyrometers. For this purpose such pyrometers as Ferry
may be used, in which the temperature is ascertained by
the color of the object heated.
RUSSIAN CARTRIDGE CASE 235
The methods of manufacture of the order of cartridge
cases must be similar to those used for the manufacture of
test consignment. In case of any alterations in the method
of manufacture, the works must inform the inspector to
that effect, and he must report the matter to the military
administration with his opinion on the value of such altera-
tion in manufacture. It is left to the discretion of the mili-
tary administration to allow such alteration or to demand
from the works the delivery of a new test consignment.
A firm which has already manufactured cartridge cases of
certain type may be released from the delivery of a test
consignment, provided the methods of manufacture have
not been altered.
Clause 3. The Acceptance of the Brass. The brass
used in the manufacture of cartridge cases must be of the
following composition :
Copper from 67 to 72 per cent.
Zinc from 33 to 28 per cent.
The proportion of other metals must not exceed 0.5 per
cent, except tin, which must not exceed 0.3 per cent.
During the manufacture of cartridge cases in the same
consignment, the variation of copper in the brass must
not exceed + 1 per cent, or 0.5 per cent compared with
the usual composition used by the works which composition
must be given to the inspector before the manufacture of
the test consignment. The method of manufacture of brass
is left to the discretion of the works. The only require-
ments are as follows:
1. The cast ingots must be annealed before first rolling.
2. All rolling must be carried out in the same direction,
thus allowing the top end of the casting always to be distin-
guishable.
The top or bottom portion of the castings must not be
used for the manufacture of cartridge cases. They must
be cut from the ingots by the works manufacturing the
brass, or the blanks for the cartridge cases must be cut at
a certain distance from both ends of the ingots. On receipt
of the brass ingots, the works manufacturing the cartridge
cases must inform the inspector to that effect, giving him
236 RUSSIAN CARTRIDGE CASE
the chemical analysis and the composition of the casting.
The consignment of the brass must be sufficient for the
manufacture from it of the whole consignment of the cart-
ridge cases. At the works which manufacture the brass,
test bars must be cast from the same furnace and from
material of the same quality, melted in a similar manner,
and stamped with the same number as the castings. This
number must be stamped at the bottom of the cartridge
case.
The brass used for tests must be submitted to the inspec-
tor in bars, and the cutting of the test disks from the bars
must be carried out under the inspector's supervision. A
few bars are to be used for the microscopical analysis. The
bars of each consignment must be stamped with a number,
which number must be stamped afterwards on the blanks
during all the drawings. This number must also be stamped
on the bottom of the case, as mentioned. These numbers
must be put by the inspector in the report together with
chemical analysis of metal, composition of casting, number
of rods delivered, time of delivery, name of brass foundry
by which the brass has been supplied (if the manufactur-
ers do not manufacture brass themselves), and the num-
ber of test disks cut. For each consignment of cartridge
cases manufactured from brass bearing a certain number,
at least one chemical analysis must be made. The brass
not answering to the requirements of the chemical analysis
will be returned to the manufacturer for re-casting.
To insure that the amount cut off from the top and bot-
tom of the rods is sufficient, the inspector must ascertain
from the first consignment the number of cartridges man-
ufactured, with defects inside as well as outside, from (1)
disks cut from upper end of rod, (2) disks cut from roller
end of rod, and (3) disks cut from the remaining part of
rod. The percentage of cartridge cases with defects, in the
above-mentioned three groups, must not differ materially
from each other. The above-mentioned tests must be car-
ried out from time to time during the manufacture of the
cartridge cases.
RUSSIAN CARTRIDGE CASE 237
The following methods can be used to ascertain that the
ends of any rod are cut off sufficiently:
1. At the center of the rod, cut a piece from the top of
the upper blank; the transverse surface of the piece must
be polished and etched with a weak solution of nitric acid ;
if the piece cut off from the top end was not sufficient, the
test piece will show, in the middle, more or less solid black
lines, inside of which, under the microscope, it will be pos-
sible to see small microscopical flaws and foreign substances.
2. The transverse test piece cut in the above-mentioned
manner must be broken in a testing machine; if the top
portion was not sufficiently cut off, the middle of the piece
will show ruptures in the metal.
Clause 4. The Arrangement of the Cartridge Cases in
Lots. The cartridge cases for delivery must be arranged
in lots. It is desirable that the cartridge cases in each lot
should be manufactured from one casting of brass metal.
If the lots are compiled from the cartridge cases of differ-
ent castings, it will be necessary to select cartridge cases for
the control test from all the castings, and the cases left
over from the lots already tested and accepted may be
placed in the new lots without repeated tests.
The dimensions of punch and die for the last drawing
must be verified from time to time. The control of the an-
nealing must be carried out by means of a pyrometer. The
cartridge cases in each lot must be inspected as follows : 1.
Outside inspection. 2. Inspection of dimensions and
weight. 3. Mechanical test of the metal. 4. Firing test.
Clause 5. Outside Inspection. The cartridge cases,
before submission for inspection, must be cleaned inside and
outside with sawdust and sand, or with brushes. The fol-
lowing defects usually occur in the cases.
1. Cracks. Longitudinal cracks chiefly occur at a dis-
tance of two or three inches from the flange, and, gener-
ally speaking, form two parallel lines very slightly notice-
able on the inner surface. Transversal cracks, slightly no-
ticeable, generally occur above the flange at the bottom ; they
are always on the outside surface and very seldom pene-
trate through. Cases with such defects must be rejected.
238 RUSSIAN CARTRIDGE CASE
2. Ruptures. These defects usually are on the outer or
inner surface of the cases and show that something is
wrong with the metal ; cartridge cases with ruptures are re-
jected without further consideration. Slight ruptures
found in the corner of the socket for the primer do not af-
fect the strength of the case and are, therefore, allowed.
3. Flaws and Fissures. Cases submitted to the inspector
after being filed and cleaned on the inner surface are re-
jected. Cases with flaws and fissures on the inside sur-
face must be submitted to the inspector separately from the
others and the filing of them must be carried out under the
inspector's supervision. The inspector has to determine to
what extent the flaws are vital. Special attention must be
paid to the flaws on the rim and on the tapered portion.
4. Scratches. These are usually due to the punch, or to
dirt which may have been in the punch. Small scratches
do not vitally affect the strength of the cases. Oases with
deep scratches are rejected, especially if on the inner side
of the case a very noticeable mark is seen, extending to the
lower part of the case.
5. Scars. Small scars which make the surface of the
case dull are allowed. Large scars on the surface giving the
appearance of a grained surface indicate too high a tem-
perature in annealing, and cases with such scars must be
rejected.
6. Dents. Dents, if rectified, are allowed on cases if
they are not important ; they are not allowed on the conical
portion or at the end of the case.
7. Goffering. Goffering on the inner surface of the case
is usually due to the uneven drawing of the metal in the
case of very rigid material ; it is due to defects in the uni-
formity of the material. Goffering does not appreciably
affect the strength of the cases, and therefore cannot gener-
ally be taken as a reason for rejection. A large amount of
goffered cases shows that there are some abnormal con-
ditions in the manufacturing of the brass or the cases them-
selves. In such cases the inspector must point this out to
the works, and if the works will not take measures to re-
move these defects the goffered cases must be rejected.
RUSSIAN CARTRIDGE CASE 239
8. Folds. Folds of metal are sometimes noticed inside
the case at the bottom and show bad manufacture. Cases
with such defects are rejected.
9. Other Small Defects. Dents at the bottom, inside,
and other small defects are allowed at the discretion of the
inspector.
Clause 6. Gaging. Cases which pass satisfactory out-
side inspection must be gaged by means of gages for maxi-
mum and minimum allowances. The dimensions gaged are
as follows:
1. All outside diameters of the cases must be gaged with
ring gages or half ring gages.
2. The inner diameter of the end of the case is gaged
with calipers.
3. All outside dimensions of the bottom of the case are
as follows :
(a) Diameters of flanges by half ring gages.
(b) Thickness of flanges with snap gages.
(c) Concentricity of the bottom of the case by ring
gage.
4. The thickness of the bottom by special gage.
5. Concentricity of the hole for the primer, by special
gage.
6. All dimensions of the hole for the primer must be
gaged with a set of corresponding gages.
7. The flatness of the surface, the absence of cuts and
hammering of the metal around the hole for the primer with
a straightedge.
8. The outline and the length by a special gage.
9. The thickness of the walls is gaged by means of a
snap gage with cut corresponding to the thickness of the
cartridge case at the end, by a small special gage with
pointer for ascertaining the thickness of the walls as well
as the depth of the cleaning away in places near the end
of the case, and by a special gage with pointer for ascer-
taining the thickness of the walls along the whole length of
the case.
For the purpose of ascertaining that the outline of the
cases is correct, the inspector has the right to select 0.2 per
240 RUSSIAN CARTRIDGE CASE
cent of the cases from the lot, choosing preferably from the
rejected cases; special attention must be paid to the differ-
ence in thickness of the walls at the lower end of the cases.
To ascertain the similarity in weight, all cases must be
,weighed ; the difference from mean weight must not exceed
the limits fixed for each caliber of the cases.
If during the preliminary examination of the cases more
than 15 per cent are found defective, as regards the metal
or dimensions, the inspector has the right to stop the further
examination of the cases submitted, and to ask the firm to
re-submit them again. If, after re-submitting, and during
the second examination of the cases, more than 5 per cent
are found unsatisfactory, the whole lot will be rejected.
Clause 7. Mechanical Tests. In the following para-
graphs are given special conditions for the acceptance of
cartridge cases for the guns of different calibers. As a
general rule, the mechanical qualities of the metal used for
cartridge cases must comply with the following conditions :
1. The rigidity of the bottom and the lower end of the
cases must be sufficient to insure the proper extraction of
the cases.
2. The rigidity of the end of the cartridge must insure
the proper grip of the shell, and for the howitzer cases must
not show any dents on the metal.
3. The rigidity of the metal along the whole length of
the case must change evenly, without sudden changes.
During the manufacture of the cases, care should be taken
to work the metal as near as possible to the lower limits of
the rigidity of the metal, as any extra rigidity affects the
strength of the case during firing and in storage.
The mechanical qualities of the cases must, as far as pos-
sible, be alike; they are tested (a) by a breaking test of the
metal used for the cases ; (b) by ascertaining that the shell
is fixed properly in the case (a casting may be used for
this purpose manufactured to the dimensions and the weight
of the proper shell) ; (c) microscopical analysis of the
metal; and (d) any other methods at the discretion of the
inspector, as, for instance, by ascertaining the hardness of
the metal, compression of the mouth of the case, etc.
RUSSIAN CARTRIDGE CASE 241
For the tensile test the inspector selects from each lot
about five cases rejected on account of the dimensions ; these
are cut in halves for the purpose of ascertaining the thick-
ness of the walls. The number of cases used for mechanical
tests may be increased by the inspector if it is required by
the quality of the material. From each case selected for
the mechanical test, three rings must be cut, one inch wide ;
one next to the flange, iy% inch above it; one from the mid-
dle of the mouth; and one immediately under the conical
portion, if such portion exists ; otherwise from the middle of
the case. The rings cut in the above manner must be cut
longitudinally and straightened by delicate hammering with
a wooden mallet or by rolling between wooden rollers. From
each strip obtained in such manner two test pieces must be
cut with a distance between marks of 1.97 inch (50 milli-
meters). The width of the test pieces must be the same.
Ten division marks must be made on the test pieces, each
division being 0.197 inch (5 millimeters). During the
mechanical test, the following data must be ascertained:
Breaking stress, total elongation, and local elongation be-
tween all division marks.
Clause 8. Firing Proof. After the examination of the
whole consignment, the inspector selects some cases for
proof by firing. The inspector chooses for the firing trials
those cases which he considers the least satisfactory. The
works have the right to re-examine the cases selected by the
inspector for firing, and remove any case selected by the
inspector ; but, in such an instance, all cases with similar de-
fects are to be rejected, and the inspector replaces the cases
removed by the firm. The works have not the right to re-
move the cases selected in the above manner more than twice
for each consignment. The firing proof of the cases must be
carried out at any place selected by the artillery administra-
tion, where the cases must be delivered by the works.
The firing proof must be carried out in a similar manner
to the test consignment, and the submitted consignment is
accepted :
1. If all cartridge cases after firing are extracted with-
out any difficulty.
242 RUSSIAN CARTRIDGE CASE
2. If no case shows longitudinal, transversal or any
other cracks, or ruptures of metal.
If during the firing trials one case shows a crack or is
difficult to extract, the works have the right to review the
consignment and submit for the firing trials a second set
chosen by the inspector. In such instances, the works have
no right to remove any case selected by the inspector for
secondary proof ; the number of cases selected for secondary
proof as well as the number of proof rounds fired may be
increased. For the acceptance of the consignment, all cases
must give satisfactory results in the second firing test. If
the two consecutive firing proofs will give unsatisfactory
results, the artillery administration has the right to cancel
the contract. The firing proof is carried out at the expense
of the government, and the cases normally used are counted
as part of the consignment. The fired cases, after re-sizing,
annealing and inspection, are submitted by the works to the
inspector, and afterwards they must be packed in separate
boxes.
The cases required for secondary proof must be at the
expense of the manufacturer.
Clause 9. Varnishing. In case of satisfactory results
of firing proof, the works varnish the cases inside as well
as outside. The varnish must be used evenly. When
scratched with a wooden point or with the finger nail, the
varnished surface must not show any impression; when
scratched with a metallic point the varnish must not crum-
ple, and must not show any cross cracks. The varnish on
the cases must not alter its appearance if placed for twenty-
four hours in water, and after removal from the water and
again dry, it must adhere so firmly as not to be removable
under pressure of the finger.
The specific gravity of the varnish must be from 0.9 to
0.94. Brass strips covered with the varnish must not show
any oxidizing action. After the heating of the varnished
strips during 24 hours in the water bath at a temperature
of 167 degrees F., the varnish, when heated, must not peel
off. For the purpose of ascertaining the character of the
reaction of the varnish, 10 cubic centimeters (0.61 cubic
RUSSIAN CARTRIDGE CASE 243
inches) of solvent must be distilled from 100 cubic centi-
meters (6.1 cubic inches) of the varnish, and the solvent
obtained in this manner, when mixed with a weak solution
of litmus, must not give an acid reaction.
Clause 10. Stamping. The cases must be stamped as
follows: On the top, the number of the consignment of
brass ; at the left, number of the consignment of the cases
and the year of manufacture; on the right, the firm's in-
itials ; at the bottom, the inspector's stamp, which must be
placed after the inspection, and the stamp which means ac-
cepted and which must be placed after the firing proof. The
letters and figures must not exceed Vs inch in height.
Clause 11. Packing. The cases, after being wrapped
in paper, are covered with straw caps and packed in strong
wooden boxes. These must be dovetailed from pine or fir
wood, with rope handles and iron bands. The lids must be
fixed with screws. The works have to pack the cases to
the satisfaction of the inspector. To ascertain the accuracy
of packing, the inspector turns over one of the boxes
chosen, and after that the case must not show any dents
or any noticeable damage to the varnish on the cases. Fifty
cases are packed in each box.
The boxes must have the following marking:
Accepted Cases: Fired Cases:
Caliber of Cases Caliber of Cases
Name of Works Name of Works
Year of Manufacture Year of Manufacture
Number of Cases in Lot Number of Cases in Lot
Number of Consignment Fired, but Good for Use
Number of Consignment
Condition for Acceptance of Cartridge Cases for 3-inch
Field Guns. The test consignment must consist of fifty
cartridge cases. The proof must be carried out from the
gun with pressure of about 15.75 tons per square inch (2400
atmospheres). Ten cases are selected from those showing
the maximum increase of diameter and are used for re-
charging; they must be re-annealed after each round; all
doubtful cases must be added to the above-mentioned cases.
Each of these cases must stand eight rounds.
244 RUSSIAN CARTRIDGE CASE
The gaging must be carried out as follows :
Dimensions in Inches
Normal Reject
1. Diameter of the case near bottom, gaged with
half ring gages 3.294 3.286
2. Diameter of flange, gaged with half ring gages 3.547 3.539
3. The outside diameter of the end, gaged with
half ring gages, and with gage inserted in
the case 3.004 3.000
4. The inner diameter of the case 2.923 2.9?7
5. The thickness of the flange 0.142 0.134
6. The thickness of the bottom, gaged with
special gage . 0.157 $+0030
"j 0.010
7. The concentricity of the hole for the primer must be gaged with
special gage.
8. The concentricity of the flange with reference to the body must
be gaged with half ring gage, the dimensions of which must be
as follows:
(a) Maximum diameter of flange.
(b) Maximum diameter of the case at bottom.
(c) Maximum thickness of the flange.
9. The outline and the length of the case must be checked by special
chamber gage. The allowance for length must be 0.010 inch.
10. The gaging of the hole for the primer is carried out by the fol-
lowing gages:
(a) Screw gages, normal and reject.
(b) Normal gage which is used for the gaging of the whole
diameter and the depth of the hole for the primer, normal
and reject.
(c) Reject gage for the flange of the primer.
(d) Reject gage for the thread.
(e) Reject gage for the plain surface of the hole.
(f) Normal and reject gages for the thickness of the hole for the
flange of the primer.
(g) Normal and reject gage for the depth of the plain portion of
the hole,
(k) Gage for the ignition hole.
11. Normal and reject gage for the height of the boss for the primer.
12. Gages, compasses and special gages for the thickness of the walls
and for the depth of filing of the inner as well as the outer
surfaces.
13. Straightedge for gaging the bottom surface of the case.
The difference in the weight of cases from mean weight
must not exceed 3 ounces.
The test pieces subjected to the tensile test must show
the following breaking stress:
(a) At the ends, 48,000 to 57,000 pounds per square
inch, with local elongation not less than 60 per cent.
(b) Next to the flange, from 64,000 to 85,000 pounds
per square inch.
(c) Next to the conical portion, not less than 52,500
pounds per square inch.
RUSSIAN CARTRIDGE CASE 245
Firing Trial. : For the firing trials, thirty cartridge
cases must be selected. These cases must be measured and
must pass a similar test to that of the test consignment,
with the following exceptions.
1. Only five cases are taken for re-proving, including
cases showing the maximum expansion, and those doubtful
with reference to their strength.
2. The cases are to be fired five times.
During the firing of the secondary proofs, as well as dur-
ing the firing of the cases selected from the lots entirely
consisting of the defective cases, the number of cases as
well as the number of re-tests may be increased to the num-
ber fixed for the test consignment.
Specifications for Primers. The charge primer consists
of brass body, detonator, bush, brass anvil, a charge of
gun powder (not polished with graphite) , a disk of saltpe-
ter-soaked tissue paper, four powder cakes, disk of salt-
peter-soaked muslin, disk of parchment, and a brass disk
bored in the center and coated outside with thick shellac
varnish mixed with cinnabar.
Detonator. The detonator consists of a small copper
cap containing a charge of 0.275 grain of the detonator
composition, covered by a thin paper parchment disk and
compressed with a pressure of 125 pounds. The thickness of
the parchment is between 0.002 and 0.0025 inch. The sur-
face of the parchment facing the composition is coated by
a thin layer of fluid shellac varnish composed as follows:
15.12 gallons of 95 per cent alcohol and 20 pounds of shellac.
The detonator composition contains 50 per cent fulminate
of mercury, 20 per cent chlorate of potassium and 30 per
cent glass ground to dust and sifted through a sieve No. 100
(100 meshes to 1 inch). To this mixture is added 0.25 per
cent of tragacanth gum and a trace of gum arabic. The com-
position is placed in the cap while moist. After compres-
sion the detonator is dried for ten days at a temperature of
88 degrees F., and twenty days at 111 degrees F. Then the
exterior surface of the parchment disks is coated with a
thick varnish composed of 0.891 gallon of 95 per cent alco-
hol, 2.75 pounds of shellac, and 0.5 pound of resin. The
246 RUSSIAN CARTRIDGE CASE
varnished detonators are dried at room temperature for five
or six days, and then undergo a final examination, in which
the defective caps will be rejected. The caps, when ready,
must have even wedges, no rents, cracks, dents or such like
defects, and the parchment disks must be placed concentric
with the edges of the caps.
Out of a lot representing a day's output (about from
10,000 to 15,000) of detonators, twenty-five are set aside
without selection, for testing under a drop weight of 13.65
ounces, falling from a height of 3.94 inches. These must
not show a single failure. If a day's output of detonators
does not answer that condition, it undergoes, after a sup-
plementary drying, a second test in double quantity. Any
lot of detonators that does not stand this test will be re-
jected and burnt out.
The tissue paper and muslin disks are soaked with a 10
per cent solution of saltpeter. The powder cakes are com-
pressed gun powder, not polished with graphite, and have a
diameter of 0.748 inch, a height of about 0.120 inch, and
weigh from 21.95 to 23.32 grains each.
Charging Primers. The charging of primers is preceded
by the examination of their bodies and other parts. The
charging is done in the following order : The detonator is
placed in the bush which is screwed onto the end into its
seat and then nipped in two places in order to prevent its
becoming unscrewed. The anvil is then screwed into its
seat, so as to press tightly on the detonator composition,
without, however, cutting the parchment disk. To inspect
the proper screwing in of the anvils, 30 primers are set
aside out of every 300, and from those the anvils are screwed
out and the detonators examined. The parchment disks
must bear clear marks of the anvils, without being cut
through.
In properly fitted primers the anvils are prevented from
becoming unscrewed by nipping them in two places. A
charge of from 10.286 to 10.972 grains of powder is placed
in the groove between the hose and the internal surface of
the body of the primer. This charge must fill the groove
to the brim. The powder is now covered with the disk of
RUSSIAN CARTRIDGE CASE 247
tissue paper soaked in saltpeter. On the top of it will be
placed four powder cakes, which will be covered first with
a disk of saltpeter-soaked muslin, then with a parchment
disk and lastly with a brass disk bored in the center, after
which the upper edge of the primer is closed in, this opera-
tion being carried out in three stages. After the first press-
ing, a proper position is given to the disks inside the primer ;
after the third (final) pressing the primer is to be gaged.
The upper side of the brass and parchment disks is var-
nished with thick shellac mixed with cinnabar.
After having been dried in the shop for 24 hours, the
primers are packed in cardboard boxes. Two such boxes,
(50 primers in each) are sealed hermetically in zinc boxes.
The proper hermetic soldering of some boxes chosen at
random will be tested. Eight zinc boxes are packed in
one wooden box, which will thus contain 400 primers.
Inspection of Primers. Bodies and other details will be
manufactured of brass, the composition of which will be
left to the discretion of the works, but on the express con-
dition that the primers will comply with all requirements
stipulated. The best results have been obtained when the
metal contained from 67 to 74 per cent of copper, and from
33 to 26 per cent of zinc.
Before beginning the manufacture of the order, the
works with which the order will be placed must deliver
a test consignment consisting of 100 primers. The test
consignment of primers after being charged must be sub-
jected to a firing trial. The conditions of this trial are
similar to those used for the trials of the complete order.
The order must be submitted in lots of 25,000 each.
The gaging of dimensions at the works manufacturing
the primers must be carried out after each separate opera-
tion of manufacture, for which approved gages and control
gages must be used. All the gages must be manufactured
by the works, with which the order for the primers is
placed, with the exception of the gage nut used for the gag-
ing of the outer thread and the check screw for same. The
last mentioned gages must be handed over to the primer
works by the proper authorities.
248 RUSSIAN CARTRIDGE CASE
The primers, before being charged, will be assembled at
the works which manufacture them, i. e., bushes and anvils
are screwed in, and the primers are delivered to the explo-
sive works in such condition. After the completion of the
manufacture of a lot of 25,000 primers, 1000 of them, chosen
at random during the manufacture, will be sent to the ex-
plosive works for inspection, for testing the rigidity of the
metal, and for preliminary tests of the metal by firing.
If, during the trial for the rigidity of the metal carried
out by the compression of 50 primers chosen at random,
more than 5 per cent show ruptures, the complete lot of 1000
primers will be returned to the manufacturers.
In the case of satisfactory results of firing trials, the
remaining 24,000 primers will be delivered to the works
intrusted with the charging.
If, after partial examination of a lot (not less than 1000
primers), more than 10 per cent of primers will be rejected
in accordance with the following two paragraphs, the
further inspection will be stopped at the charging works,
and the whole lot will be returned for resorting.
When inspecting primers, the following defects are not
allowed : ruptures, blow-holes, fissures, flaws, sandy surface,
dirt, oil, dust, shavings, dents on the bottom surface of the
flange, dents at the bottom of the charge chamber, and con-
siderable crumbling of threads (more than one-fourth of a
thread) . The examination of the bottom surface for even-
ness must be carried out by spinning the primers on a pol-
ished steel plate. The primers which will not spin must be
rejected.
The primer chambers must be varnished. The anvils
must not show any flaws and fissures at their striking edge
and at the threads. The striking edge must not be sharp,
to prevent the cutting through of the parchment disks of
the detonator; generally speaking, the anvil and the bush
must also answer all the requirements of the preceding
paragraph.
Gaging. One hundred primers complete from each lot
must be gaged. Special attention must be paid to the fol-
lowing points :
RUSSIAN CARTRIDGE CASE 249
(a) All primers to be screwed into gage without being
specially loose.
(b) The thickness and the outer diameter of the primer
head must not exceed the specified maximum dimensions,
thus securing the proper fit of the primer flange in its seat
in the cartridge case.
(c) The height of the boss inside the primer must be
strictly in accordance with the allowance given.
(d) The inner thread of the boss must be strictly in
accordance with the gage.
(e) The seat for the detonator and the hole in the bush
must be correct and in accordance with the gage.
(f) The thickness of the bottom of primer (0.067 to
0.077 inch) must be in accordance with the gage.
The anvils and bushes must screw and unscrew easily,
without being loose and must be interchangeable. After
charging, all primers will be inspected with regard to their
height, and gaged outside. In case of unsatisfactory results
in gaging (rejected primers exceeding 3 per cent) an addi-
tional 100 primers must be chosen for the same purpose, and
in case the results are the same, the whole lot will be re-
turned to the works manufacturing the primers for re-
sorting.
Firing Trials. Fifty primers out of 1000 delivered from
a lot of 25,000, after being charged, are tested with refer-
ence to the quality of the metal, by firing with increased
charge at a pressure of 2400 atmospheres (15.75 tons per
square inch). These primers, after the test, should not
show any breakage (after being unscrewed) through cracks
and flaws, the presence of which would mean that the gas
escaped through the base of the primers. The escape of
gases leaving a residue between the side surfaces of the
primer flanges and their seating is allowed on not more
than 30 per cent of the primers subjected to firing test
from new 'cartridge cases; in the case of using fired cart-
ridge cases, no attention must be paid to the presence of the
above-mentioned residue.
Non-through cracks are allowed on not more than 2 per
cent of tested primers; in the case of a larger percentage,
250 RUSSIAN CARTRIDGE CASE
but not exceeding 4 per cent, the whole lot must be resorted
and retested. The recurrence of 2 per cent of non-through
cracks in the second test may not be taken as a reason for
the rejection of the whole lot; 50 primers must be used for
the second test. In the case of the absence of above-men-
tioned defects, only those primers will be considered satis-
factory which, after firing, can be removed from the cart-
ridge case by hand or by an ordinary spanner.
The serviceableness of the primers is determined by firing
50 primers chosen at random from the complete lot of
25,000 charged primers. The conditions just laid down
hold good for this trial also. In addition to this, no com-
plete misfire must occur; not more than two primers may
misfire once each, with lock in proper order. (Before firing,
the tension of the main spring and the protrusion of the
firing pin must be verified.) A second test may be carried
out if during the preliminary test defects occur. The sec-
ond test must be carried out on double the number of
primers taken at random, i. e., on 100 primers. During
second test the same conditions as laid down for the first
test hold good. Primers passing successfully the first or
second firing tests are accepted for the service. A lot of
charged rejected primers must be destroyed and the metal
scrapped.
In addition to the firing tests, the following test must
be carried out by the works intrusted with the charg-
ing of primers to determine the correctness of charging:
1. One per cent of a day's output must be tested under a
drop weight of five pounds falling from a height of 0.39
inch with flat firing pin 0.25 inch in diameter ; during this
test no primer must detonate. Primers having passed this
test and not showing any noticeable mark on the base must
be recharged and added to the lot. 2. When testing 0.5
per cent of each day's output under a drop weight of five
pounds, falling from a height of 5.9 inches, with firing pin
of an approved pattern, no primer must fail to explode.
CHAPTER X
SPECIFICATIONS FOR BRITISH 18-POUNDER
QUICK-FIRING SHRAPNEL SHELL
The following paragraphs, abstracted from the official
specifications, give all the information contained in these
specifications relating to the manufacture and inspection of
the British 18-pounder, quick-firing shrapnel shell.
Body. The body of the shell is made of cast or forged
steel of the best quality for the purpose, turned or ground
to the form and dimensions, and having the edge of the
base rounded. If made of cast steel, the casting must be
clean, of uniform transverse thickness, free from flaws,,
blow-holes, and other defects. The use of chaplets is pro-
hibited. If made of forged steel, the body must be forged
hollow, and free from forging marks and flaws. Should the
shells be subjected to heat-treatment, this must be carried
out in batches consisting of shells of the same cast. An
undercut groove, with two projecting waved ribs, will be
turned on the body. Three chisel cuts may be made across
the waved ribs in the groove for the driving band, at an
angle to the longitudinal axis of the projectile to allow the
air in the channels between the ribs to escape when the band
is being pressed on. The top is threaded to receive the
socket, and a groove for the fuse cover provided. The steel
body alone must weigh 6 pounds 5 ounces 12 drams, plus or
minus 2 ounces.
Driving Band. The driving band is made from a ring
of drawn or electro-deposited copper, pressed into, and in
contact with, the bottom and undercut of the groove in the
shell all around, and accurately turned to the form required.
The weight must be 4 ounces 12 drams, plus or minus 2
ounces.
Socket. The socket is made of composition metal,
known as Class "C," threaded externally below the shoulder
to fit the body, and internally to receive the fuse, the bottom
being bored to receive the top of the central tube. The
251
252
BRITISH SHRAPNEL SHELL
junction of the socket and central tube is soldered to pre-
vent the resin getting into the tube and socket. A hole is to
be bored in the side, threaded and fitted with a steel fixing
screw. The weight must be 8 ounces 8 drams.
Central Tube. The central tube may be made of brass,
copper, delta metal, or gun metal. The lower end is to have
REMOVE SHARP
INNER E
OF SCREW HOLE
SOLDER JUNCTION
BETWEEN SOCKET
AND CENTRAL TUBE
TUBE TO BE FLUSH
WITH BOTTOM OF
FUSE SOCKET
RESIN
Machinery
Fig. 1. Construction of British 18-pounder Quick-firing
Shrapnel Shell
a shoulder to rest on, and to be threaded to enter the steel
disk, the bottom being reduced in diameter to fit the neck
of the cup. Weight, 2 ounces 12 drams.
Steel Disk. A steel disk, of the form shown in Fig. 2,
will rest on the shoulder in the bottom of the body, a hole
BRITISH SHRAPNEL SHELL 253
being bored and threaded through the center of the disk
to receive the central tube. Weight, 9 ounces 8 drams.
Tin Cup. The cup in the base of the shell to contain
the bursting charge will be made of tinned plate to the form
and dimensions shown in Fig. 2, the parts being soldered
together. Weight, 1 ounce 12 drams.
Gages. Contractors may send their gages at any time
to the chief inspector, Woolwich Arsenal, London, England,
to be checked and compared with the standard gages.
Screw Threads The screw threads must, unless other-
wise stated, be of "the British standard fine screw thread,
and conform to the chief inspector's standard gages.
Preliminary Examination of Contractor's Work. The
bodies, after completion of machining, will be submitted at
the contractor's works, to an inspector, for preliminary ex-
amination. Bodies made of cast steel must also be submitted
for a hydraulic test under a pressure of 100 pounds per
square inch. Any shell which shows the slightest leak, or
fails to satisfy the conditions, will be rejected.
Assembling. The tin cup, steel disk, and central tube
are to be placed in position and the shell filled with mixed
metal bullets, 41 per pound (composed of seven parts of lead
and one of antimony), the interstices between the bullets
being filled with resin, which must be perfectly pure, and
filtered when in a liquid state through a sieve having 32
meshes per inch. The socket is then screwed onto the body
as tightly as possible, the threads having been previously
coated with Pettman's cement or red lead.
Marking and Plugs. The shells are to be marked on the
side, above the driving band. Plugs for the protection of
the fuse holes in transit will be supplied, free of charge,
on demand, by the ordnance officer to whom delivery is to
be made.
Delivery. (a). The shells will be covered with a thin
coating of vaseline or other similar anti-corrosive grease,
which must be of such a nature as not to interfere with the
gaging, and they will then be delivered unpainted, for in-
spection and proof. The shells must be perfectly cleaned
out, empty, complete in every respect, and dry internally.
254 BRITISH SHRAPNEL SHELL
(b). Such marking as may be necessary to identify the
steelmaker's cast number, and, in case of heat-treatment,
the batch number, must be maintained by the contractor
upon every shell throughout manufacture, (c) . The shell
must be delivered in lots for purposes of proof. A lot for
this purpose will consist, as far as possible, of shells of
the same cast, and, when heat-treatment is employed, of
shells of the same batch number, and must not contain
more than 121 shells, (d). When the number of shells in
a cast or batch is less than 100, two casts or batches may be
grouped together for this purpose.
Main Examination after Delivery. (a). Any shell of a
lot which fails to pass the chief inspector's gages, or fails to
satisfy the chief inspector of its serviceability, will be re-
jected, (b). If at any time during the examination it is
found that defects of any nature, other than errors of ma-
chining, which involve rejection of defective shells, amount
to 5 per cent of the number of the shells in the lot, the "lot"
will be rejected, (c). One or more shells selected from
the lot will be taken to pieces, and the body broken, if nec-
essary, to ascertain that the details of manufacture and
component parts are correct, and that the material is sound.
Should they be incorrect, or the material unsound, in any
particular, the lot will be rejected. The driving band will
be cut out, and should it appear not to have been pressed
thoroughly home into the undercut and groove throughout,
the lot will be rejected, (d). If, at any time during the
examination of a lot, it is found that 5 per cent of the shells
in the lot depart from the approved design, further exami-
nation of the lot will be suspended. The whole of the lot
must be re-examined by the firm and those shells which are
incorrect eliminated. Those shells in which the departure
can be rectified may be brought to the approved design by
the firm. The lot may then be re-submitted.
Tests. At least 1 per cent of the shells of every cast
will be subjected to tensile tests. Test pieces will be cut
from the shell blank, or from the finished shell at the option
of the chief inspector, and must be capable of standing the
following minimum tests :
BRITISH SHRAPNEL SHELL
255
Tenacity, Tons per
Square Inch
Elongation in a Test Piece 2 Inches
in Length, or such Piece as can be
cut from the Shell, provided that
Length
Yield
Point
Breaking
Stress
j/ Area
36
56
8 per cent
If any one or more of the conditions in this clause are not
complied with, the lot, or lots, of shell affected, will be re-
jected, and must not be re-submitted. The contractor will
supply, free of charge, the necessary "Class C" metal for
testing, if requested by the chief inspector to do so. The
pieces ishould not be less than 7 inches in length, nor less
than 1 inch in diameter, and will be required to stand the
following test:
Tenacity, Tons per
Square Inch
Elongation in a Test Piece 2 Inches
long and 0.564 Inch in Diameter
Yield
Point
Breaking
Stress
6
12
10 per cent
Proof. (a). A percentage of the shell will be fired for
recovery from an 18-pounder Q. F. gun, with such a charge
as will give a chamber pressure not less than 15 tons per
square inch. Should the shell so fired set up above the high
diameter of body, or break up in the gun, or should any
portion of the driving band separate from the shell before
first graze or impact, or should the recovered shell show
that the shock of discharge had distorted the disk support-
ing the bullets, or cause such alteration of the internal parts
as would interfere with the correct action of the shell, or
should any of the components be incorrect, the lot will be
rejected, provided always that the pressure did not exceed
the specification proof pressure by 0.5 ton. If the pressure
did exceed this limit, a second proof must be taken at the
government's expense before the lot is rejected. The pres-
256
BRITISH SHRAPNEL SHELL
0.2^ |*-
-*, u-,,-0.225" BODY. FORGED STEEL
i-H U?* 1 0.401*-
ENLARGED SECTION SHOWING
g"g COPPER DRIVING BAND g o
o S
- -
FUSE SOCKET, BRASS
H 0.345 If X, 3.65'.T0.01^
.. ., ^ i I ' ^ 3.300.01- tf
H.0.225 |r> | LO_ i -X^l,^ 1
ZOT.P^H. hMiKr;o"C''/\ si
BRITISH!
(WHIT.)~
FIXING SCREW, STEEL COPPER DRIVING BAND
ELECTROLYTIC COPPER
Machinery
Fig. 2. Details of British 18-pcunder Shrapnel Shell
BRITISH SHRAPNEL SHELL 257
sure of the round, if not taken, will be assumed to be that
of the last round fired with the same charge in which pres-
sure was taken. Further, should the shell be reported un-
steady in flight, and be found on recovery to be without
its driving band, or with the driving band loose or slipped
in its seating, then the driving band of a similar number
of shells to that taken for firing proof may be cut out to
ascertain whether they have been properly pressed on; if
they have not been pressed down to the satisfaction of the
chief inspector, the lot will be rejected. If found correct,
such shells will be rebanded by the contractor free of charge.
(b). The shells fired for proof may, after recovery, be
broken to ascertain the soundness of their material. Should
any of the material be unsound in any respect, the lot will
be rejected.
Re-submission. (a). A rejected lot must not be re-
submitted unless the rejection is due to failure of the driv-
ing band, or to rectifiable gaging defects, (b). Shells
put out at any period of inspection for remediable defects
may be re-submitted for further examination after the de-
fects have been rectified. It is to be understood that the
examination of such shells at that time will be incomplete,
and that they are liable to rejection after rectification, (c) .
If the contractor wishes to re-invoice a lot rejected for fail-
ure of driving bands, he must remove the shells and re-band
them before they are again submitted, (d). Rejected
shells will, if considered necessary, be marked with a small
rejection mark, so that they can be readily identified if re-
delivered.
Replacement of Proof. The contractor will be required
to replace, free of charge, all shells expended in proof and
examination, which, whether fired or otherwise tested, will
be the property of the government.
Packing. All packages are to be so marked that the
goods contained therein may be readily identified with the
invoice. Unless it is specified in the contract that the pack-
ing cases or other packing material are to become the prop-
erty of the war department, they will remain the property
of the contractor, who is responsible for their removal.
258 BRITISH SHRAPNEL SHELL
Should they not be removed within two months of the ac-
ceptance at the stores, they will be disposed of, and under
such circumstances the contractor will not be entitled to
make any claim for compensation. The packing cases must
be marked "Returnable" or "Non-returnable."
Inspection. The shells may be inspected at any time
during manufacture by, and after delivery will be subject
to testing by, and to the final approval of, the chief inspec-
tor, Royal Arsenal, Woolwich, England, or an officer deputed
by him. In cases of defects occurring in manufacture
which necessitate repairs, the contractor shall bring the
same to the notice of the inspecting officer, and shall obtain
from him written authority to proceed with such repairs as
may entail patching, burning, electric welding, or other
similar processes.
WEIGHT OF 18-POUNDER SHRAPNEL SHELL PARTS
Weights (avoirdupois)
Part Pounds Ounces Drama
Driving band
4
12 C 2 Z '
Metal socket
8
8
Steel disk . ...
9
8
Brass tube
2
12
Tin cup
1
12
Bullets, about 327 of
pound
alloyed metal, 41 per
7
14
13 1 / 2
Resin .
13
11
Total weight empty
(unpainted)* 16
13
Sy 2 -+-11 drams
Bursting charge ...
2
8
Paint
5y 2
Fuse ...
1
7
10
Total weight
. 18
8-^5 drams
* To regulate weight of shell, a few buckshot may be used.
Plug for Fuse Hole. The plug is to be made of a cop-
per alloy, and to the form and dimensions shown on the
drawing, threaded externally on the body, and a square re-
cess, tapered, is to be formed in the top. The screw
threads must, unless otherwise stated, be of the British
standard fine screw thread, and conform to the standard
gages of the chief inspector, Royal Arsenal, Woolwich, Eng-
land. Contractors may send their screw gages to the chief
inspector, to be compared with the standard gages.
BRITISH SHRAPNEL SHELL 259
Any plug of a delivery which fails to pass the inspecting
officers' gages, or shows flaws or sponginess on the surface,
or fails to satisfy the chief inspector, Woolwich, as to its
serviceability, will be rejected. If at any time during the
examination it is found that defects of any nature, other
than errors of machining, which involve rejection of the
defective plugs, amount to 5 per cent of the number of plugs
in the delivery, the whole order will be rejected. If at any
time during the examination of a delivery it is found that
5 per cent of the plugs in the delivery will depart from the
approved design, further examination of the plugs will be
suspended; the whole of the delivery must be re-examined
by the firm, and those plugs which are incorrect to design
eliminated. Those plugs in which the departure can be rec-
tified may be brought to the approved design by the firm.
The delivery may then be re-submitted for examination.
The contractor will be required to replace free of charge all
plugs expended in test and examination, which will become
the property of the government.
CHAPTER XI
SPECIFICATIONS FOR BRITISH COMBINATION TIME
AND PERCUSSION FUSES
The following specifications, abstracted from the official
requirements relating to British "Mark I" (No. 85) combi-
nation time and percussion fuses, give the general infor-
mation required in the manufacturing and inspection of
these fuses. These specifications, in conjunction with the
very complete illustrations, Figs. 1 to 6, inclusive, of the de-
sign and details of the British fuse, give all the essential
data required.
Components. The fuse consists of the following parts:
Body, top and bottom composition rings ; cap with set-screw ;
base plug with screw plug; time detonator pellet in two
parts ; percussion pellet with sleeve and firing pin ; detona-
tors; four spiral springs; brass and steel pins; onion skin
paper; unbleached muslin; felt cloth and brass washers;
brass and tin-foil disks ; suspending ring for time pellet ; and
onion skin paper patches.
Metals. The body and composition rings are to be made
of bronze or metal known as "Class B ;" the time detonator
pellet and percussion pellet to be erf hard-rolled brass; the
percussion firing pin pivot, of steel, phosphorized or blued ;
the time and percussion firing pins, of bronze or "Class B"
metal; all other parts of the fuse, except where otherwise
stated, of metal "Class C," or hard-rolled brass. The con-
tractor must supply the necessary metal for testing, free
of charge.
Metals designated by "classes" are copper alloys, the
compositions of which are left to the discretion of the mak-
ers providing the metals conform to the above tests.
Before proceeding to manufacture, the material must be
submitted to the inspecting officer for mechanical test.
When practicable, test pieces should not be less than 7 inches
in length nor less than 1 inch in diameter, and will be re-
quired to stand the following minimum tests:
260
BRITISH COMBINATION FUSE
261
Metal
Tenacity, Tons per
Square Inch
Elongation in Per Cent in such
a Test Piece as can be fur-
nished, provided that
Length
Yield
Point
Breaking
Stress
I/ Area
Bronze . . ....
13.5
12
6
6
27
20
12
12
20
30
10
10
Class "B"
Class "C"
Hard-rolled Brass . . .
Body. The body is to be turned all over, and threaded
externally at the upper and lower ends, a bevel being formed
at the junction of the stem and the flange. The stem is
to be bored, and a hole drilled at the bottom of the bore
to receive the time firing pin. The upper surface of the
flange is to be grooved. The interior is to be bored out to
form a chamber for the reception of the percussion arrange-
ment and threaded for the base plug; a hole is to be bored
and threaded at the bottom of the bore to receive the per-
cussion detonator holder. An annular recess is to be made
for the magazine. Communicating holes are to be drilled
as follows :
(a) At an angle to the top surface of the flange.
(b) Vertically from the magazine recess.
(c) Horizontally at the top of the detonator recess.
(d) At an angle to join (b) and (c).
(e) At an angle from outside to bottom of recess in
stem.
Holes (c) and (d) are to be closed by plugs driven in
and secured by punch stabs. Two slots are to be cut in the
flange as shown in Fig. 2, and an elongated hole made to
receive a stop pin, which is to be secured by a small pin,
driven in. A setting mark is to be cut on the edge of the
flange.
Top Composition Ring. The ring is to be turned all
over, and bored to fit the stem of the body. A groove is to
be formed in the under side for the composition, and a re-
cess made as shown in Fig. 2, three holes being drilled from
the upper surface into the recess. A hole is to be drilled
262
BRITISH COMBINATION FUSE
through the ring between the ends of the composition chan-
nel, and recessed. A recess is to be formed in the bore,
from which a flash hole is to be drilled at an angle commun-
icating with one end of the composition channel, a vertical
escape hole being made from the top surface to the flash
hole. An indicating mark is to be made on the outside of
13)
Machinery
Fig. 1.
British "Mark I" (No. 85) Combination Time and Percussion
Fuse Modified Form of American 21 -second Fuse
the ring. Two holes are to be bored between the ring and
the stem of the body, into which pins are to be inserted to
retain the ring in position. The ring is to be made 0.020
inch thicker than the dimension given on the drawing, and
faced off to thickness after powder is pressed into the
groove.
Bottom Composition Ring. The ring is to be turned all
BRITISH COMBINATION FUSE 263
over and bored to fit the stem of the body, the upper surface
being grooved. A groove is to be formed in the under side
for the composition, and an annular recess made, three holes
being drilled from the upper face into the recess. A hole
is to be drilled in the ring from the under side between the
ends of the composition channel. An escape hole is to be
drilled, at an angle, from the end of the composition channel
to the annular recess, and a recess made to receive the clos-
ing disk. A hole communicating with the groove and the es-
cape hole is to be drilled at an angle to the top surface to
receive a powder pellet. A hole is to be drilled and recessed
for a setting pin, which is to be secured by a small pin
driven in. The ring is to be graduated from "0" to "21.2 ;"
each division, after the first, is to be sub-divided into five
parts. A line to denote safety position is to be marked.
The marking is to be blackened with japan black thinned
with spirits of turpentine, except the mark denoting the
safety point, which is to be colored red.
Cap with Set-screw. The cap is to be machined all
over, and recessed internally to receive the time detonator
pellet. The lower part of the recess is to be threaded to
screw over the stem of the body. Two slots are to be made
in the cap to receive a key, and a hole is to be drilled through
the side and tapped to take a brass set-screw. A groove is
to be made near the top, which is to be partially closed by
spinning over the edge. Four escape holes are to be drilled
at an angle from the recess on the under side, into the
groove.
Base Plug. The base plug is to be threaded externally
to fit the bottom of the body. Two holes are to be drilled
in the under side to facilitate assembling, and a central
recess formed with a seating to receive a brass washer with
a muslin disk. Six holes are to be drilled at an angle from
the upper surface into the lower recess, and a hole drilled
and tapped in the bottom to take a screw plug. This plug
is to be threaded externally to fit into the bottom of the
base plug.
Time Pellet and Detonator. The pellet is to consist of
two parts, which are to be turned and bored, the parts be-
264
BRITISH COMBINATION FUSE
ing screwed together to secure the detonator. A screw-
driver slot is to be made in the top surface, and a seating
Fig. 2. Details of British Combination Fuse
formed on the outer surface for the suspension ring. The
detonator is to be turned all over and recessed, four fire
holes being drilled through into the recess. The recess
BRITISH COMBINATION FUSE 265
is to be coated with non-acid paint and charged with 0.45
grain of the following composition (giving parts by weight) :
Glass 50
Fulminate of Mercury 40
Chlorate of Potash 20
Sulphide of Antimony 30
Shellac (dry) 2.8
The ingredients are to be thoroughly pulverized, except-
ing the fulminate, mixed dry, and then covered with alco-
hol. The fulminate will then be added and the whole thor-
oughly mixed. The composition is to be covered with a
brass disk secured by shellac. The recess in the plug is to
be coated with a composition of shellac and rosaniline and
filled with 11/2 grain of shrapnel powder compressed with
a total pressure of 60 pounds. The detonator is to be in-
serted in the holder, and secured in place by the screw plug,
the two being locked together by a small brass pin.
Percussion Pellet. The percussion pellet is to be ma-
chined all over, two holes being bored in the upper surface
and a slot cut to receive the firing pin. Two holes are to
be drilled at right angles to the slot and parallel to the flat
surfaces, one to receive the pivot for the firing pin and the
other for the centrifugal bolts. The sleeve is to be ma-
chined all over, and is to be a driving fit on the pellet. Two
spiral springs and two small pellets, and a pivot pin for the
firing pin, are to be provided. All parts, except the pivot
pin, are to be tinned all over. The parts are to be assem-
bled, and a hole drilled into the sleeve and pellet, and a
small brass pin driven in.
Percussion Detonator and Holder. The percussion de-
tonator is to be turned and recessed on both sides, two flash
holes being drilled between the two recesses. The smaller
recess is to be charged with 0.45 grain of the following
composition (the figures giving parts by weight) :
Chlorate of Potash 43.19
Sulphide of Antimony 21.5
Sulphur 7.5
Glass 10.5
Shellac . 1.7
266
BRITISH COMBINATION FUSE
0.32 0.001,, 0.0015
[< K- /NOTE: TIME T
aMiaowJ U_ || ^MiSS6
_ T J i jJLwesR
..IF
- - 0.002
0.1010.003
I
GROOVE POWDER,
SEE SPEC.
DRILL 0. 073
iFTER ASSEMBLING
SECTION A-A
THROUGH
LOCATING HOLE
POLISH AND LACQUER
THIS SURFACE
TIME AND PERCUSSIO
TOP RING
O v^ ^ >j I f M"J I
30- ^""^ 30^_ A lK0.22>i| 36 THDS.
_^^^_2^/ , afi-VALd I X-*-STO.
i*l
j COAT WITH COMPOSITION OF
ROSANILINE
BOTTOM CLOSING SCREW
BRASS
0.064 DIA., 0.10 DEEP, DRILL AFTER
OCATE AND DRIl
AFTER ASSEMBLING
CONCUSSION PLUNGER CUP
BOTTOM CLOSING SCREW PLUG
ONE BRASS ^__g
8 -H
CONCUSSION PLUNGER CU
ONE BRASS
Fig. 3. Details of British Combination Fuse
BRITISH COMBINATION FUSE 267
The ingredients are to be thoroughly pulverized and
mixed dry. Alcohol will be added to dissolve the shellac.
The detonator will be formed by pressing the mixture, while
in a plastic state, into the recess. On the evaporation of
the alcohol the composition should adhere strongly to the
metal. A brass disk, 34 in Fig. 5, is to be secured over
the composition with shellac. The larger recess is to be
varnished with a composition of shellac and rosaniline, and
4 grains of shrapnel powder compressed into it with a pres-
sure of 127 pounds and covered with a disk of tin foil, shel-
lacked on. The holder is to be threaded externally to fit in
the body, and recessed to receive the detonator, a central
hole and two key-holes being made.
Pellets. The powder pellets are to be made to the
shapes shown in Fig. 5. Pellets 33 and 35 are to be made
from compressed unglazed black powder, with clearance
holes as shown ; pellets 32 and 36 are to have the clearance
holes filled with 0.05 and 0.02 grains, respectively, of gun-
cotton.
Percussion Springs. The springs used in the percus-
sion plunger must be made to the form and size shown in
Fig. 5, and tinned. The percussion safety pin spring (21)
is to be made from 0.012 inch diameter brass wire, tinned,
and wound so as to give a free height of 0.150 inch 0.030
inch, and at such a spacing as to give 44 coils per inch.
The percussion restraining spring (30) is to be made from
0.015 inch diameter brass wire, tinned, and wound so as to
give a free height of 0.500 inch 0.050 inch, and at such a
spacing as to give 36 coils per inch. This spring is to have
a maximum resistance of 1.65 and a minimum of 1.5 ounce
at an assembled height of 0.370 inch.
Suspending Ring. The suspending ring for time deton-
ator pellet is to be made of brass wire. The ring is to be of
such strength that when tested with steel counterparts of
the stem and pellet, the latter is forced through the ring
with a deadweight load of from 69 to 77 pounds.
Cloth Washers. The cloth washers are to be made from
waterproofed felt cloth, with holes cut in them. The body
and graduated time train washers 16 and 17, respectively,
268
BRITISH COMBINATION FUSE
SPUN OVER
AMD TRIMME
0. 166 0.002 -~t |\ 0. 166 O.OOS
^MfeSVMa"
BOTTOM CLOSING SCREW DISK
ONE-UNBLEACHED MUSLIN SHEETING
SHELLACED
BOTTOM CLOSING SCREW WASHER
SHEET BRASS
SHELLACED ON BOTTOM OF GROOVE COVER
CLOSING SCREW DISK | ONE -ONION SKIN PAPER
H SHELLAC
AFTER GROOVE
PERCUSSION PRIMER CLOSING DISK
ONE TINFOIL
0.875- , , :
K0.2>J0.14<- p| N _oNE BRASS
0.064 DIA. 0.15 LONG
1.152 0.003 H DRIVEN IN
CONCUSSION PRIMER DISK
ONE-SHEET BRASS
SHELLAC ON PRIMER
TIME AND PERCUSSION BOTTOM RING
Machinery
Fig. 4. Details of British Combination Fuse
BRITISH COMBINATION FUSE 269
which are shown in Fig. 5, are to be subjected to a pressure
of approximately 10,000 pounds per square inch after as-
sembling, before closing cap is screwed on and adjusted.
Lacquering and Polishing. The exterior surfaces of
the fuse are to be polished and lacquered with a lacquer
consisting of 1 pound of seedlac, 8 ounces of turmeric, and
8 pounds (1 gallon) of methylated spirits. The groove in
the top and bottom composition rings, the magazine recess
in the body, the powder channels and groove in the base
plug, and the powder chambers of time detonator and per-
cussion detonator holder, are to be lacquered with a lacquer
consisting of 10 grains of rosaniline, li/ 2 pound of pow-
dered shellac, and 1 quart of methylated spirits.
Screw Threads. The screw threads must, unless other-
wise stated on the drawing, be of the British standard fine
screw thread, and conform to the standard gages of the
government inspector. For fuses not made in England,
the British standard threads will not be insisted upon, ex-
cept for the large thread on the body.
Time Arrangement The grooves on the under side of
the composition rings are to be charged with 56 grains of
No. 22 meal powder compressed at 68,000 pounds per square
inch ; the rings are then to be faced off, and the holes at the
ends of the channels drilled. The onion skin paper wash-
ers are to be secured to the surfaces by shellac. Perforated
pellets of black powder are to be inserted in the flash hole
in the top ring, escape hole and flash hole in bottom ring,
and flash hole in the body, the pellets for escape hole in bot-
tom ring and flash hole having the perforation filled with
loose guncotton. The space at the end of the channel in
the bottom ring is to be filled with loose meal powder.
An onion skin paper patch is to be secured over the flash
hole in top ring, and the escape hole in bottom ring closed
by a brass disk secured by two center punch holes, and
coated with shellac. The cloth washers are to be secured!
on the upper faces of the body and the lower time ring with
fish glue, and subjected to a pressure of 10,000 pounds per
square inch.
270
BRITISH COMBINATION FUSE
-*>. i<-ao8 0.003,
CONCUSSION RESISTANCE RING
BOTTOM RING WASHER
ONION SKIN 0.0015 THICK,
, U_ 0.72 0.001 _>1
STAMP WITH Jj LETTERS
AND FIGURES, >^ ~*0.156$!>.Q02\
TOP RING WASHER
ONION SKIN 0.00 1 5 THICK,
0.54 t O.QQ2 i
FTER ASSEMBLING TO PERCUSSION PLUNGER
PERCUSSION PLUNGER HOUSING
ONE - BRASS -TINNED
0.165
0.002
LOCATE AND DRILL AFT
ASSEMBLING TO PERCUSSION
PLUNGER HOUSING PERCUSSION PLUNGER
PERCUSSIO^N RESTRAINING PERCUSSION FIRING PIN FULCRUM PERCUSSION
SPRING HOUSING ONE-STEEL DRILL ROD SAFETY PIN
TWO-BRASS TINNED ^,0 TWO- BRASS-TIN NED
.uii^ ss&tsfjs AjajLs&s! ,.m'
36 COILS PER INCH T
PERCUSStON
RESTRAINING SPRING
TWO-BRASS WIRE-TINNED
PERCUSSION PRIMER
ONE-BRASS
TIME TRAIN RING PELLET
ONE-COMPRESSED UNGLAZED
BLACK POWDER
PERCUSSION PRIMER DISK
ONE-SHEET BRASS
ONE-COMPRESSED UNGLAZEC
BLACK POWDER
USED IN GRAD. TIME TRAIN RING
Machin
Fig. 5. Details of British Combination Fuse
BRITISH COMBINATION FUSE 271
Assembling and Closing. The different parts of the
fuse are to be put together as in the assembly view, Fig. 1.
The cap is to be screwed down so that a turning moment of
325 25 inch-ounces will just turn the ring, the cap being
secured by means of a set-screw. The bench or table upon
which the tensioning apparatus is fixed is to be jarred by
tapping with a mallet to assist the turning of the ring. The
base plug is to be screwed into the body, and the magazine
filled with fine-grain powder through the filling hole. The
bottom of the fuse is to be coated with shellac varnish.
Delivery. The fuses are to be delivered in lots of 2000,
an additional 40 being supplied free, for purposes of proof.
In the event of further proof being required, the fuses will
be taken from the lot.
Proof. The fuses selected for proof will be tested as
follows :
(a) Ten will have the percussion arrangement removed,
and will be tested to determine the mean time of burning
at rest. The time train will be set at the highest gradua-
tion mark. The mean time of burning, set full when cor-
rected for barometer, will be 22.9 seconds 0.4 second.
The constant to be used, when correcting for barometer, is
0.023 of the mean time of burning, for every inch the
barometer reads above or below 30 inches, being plus when
above and minus when below. The difference between the
shortest and longest time of burning is not to be more than
0.5 second. If the lot fails to pass this test, a further proof
will be taken; the fuse must burn within the limits speci-
fied above, otherwise the lot will be rejected. Should the
detonator fail to ignite the time ring, a second proof will
be taken ; should a similar failure occur at second proof, or
should there be more than one such failure at first proof,
the lot will be rejected.
(b) Twenty fuses will be fired, at the same elevation, in
any of the following guns, with full charges, and the time
of burning noted. The requirements as to the result of the
firing with the fuses set at different graduations are as
given in detail in the following :
272 BRITISH COMBINATION FUSE
1. The mean difference from the mean time of burning
of the 20 fuses is not to exceed :
( if set full 0.14 second
In 18-pounder guns j if set 16 . n second
T 10 , ( if set full 0.2 second
In 13-pounder guns j
if set 14. . . .0.13 second
The difference between the longest and shortest fuse is
not to exceed :
if set full 0.75 second
or omitting one fuse. . . .0.6 second
if set 16 0.6 second
or omitting one fuse. . . .0.5 second
if set full 0.9 second
or omitting one fuse .... 0.7 second
if set 14 0.7 second
or omitting one fuse. . . .0.5 second
In 18-pounder guns
In 13-pounder guns
2. If there is one blind fuse, a second proof will be taken.
If there is a blind at second proof, or more than one such
failure at first proof, the lot will be rejected.
(c) Five fuses from a lot will be tested, in shrapnel
shells, by firing them set at "0" from a gun with a muzzle
velocity of 1500 to 1800 feet per second. The fuses should
burst the shells at from 5 to 50 yards from the muzzle of
the gun. Should there be a burst in the gun, the lot will
be rejected. Should any fuse fail to act within 50 yards,
second proof will be taken; should a similar failure occur
in the second proof, or should there be more than one such
failure at first proof, the lot will be rejected.
(d) Five fuses from a lot will be tested in common
shells by firing them over sand, at such an elevation that
the angle of descent will not be more than 4 degrees. When
one only of a set of fuses so fired fails to burst on first graze
the lot will be accepted without further proof; if there be
more than one failure to burst on graze in the second proof,
the lot will be rejected. The fuses must burst at the point
of impact. For percussion proof the time ring is to be set
on the bridge.
BRITISH COMBINATION FUSE
273
(e) A premature explosion due to the fuse in any of
the foregoing proofs will cause the rejection of the lot.
(f) Should any other gun be introduced for proof of
this fuse, which differs from the above guns in either
muzzle velocity or twist of rifling at muzzle, the above con-
ditions will be subject to modification.
(g) If, in the proof of any delivery, defects are found
involving the serviceability of fuses, additional proof may
be taken from any other delivery not finally closed, to ascer-
[< 2.28 :0 - 02
---9.9 0.03
SOLDERING STRIP
ONE-SHEET BRASS
CENTERING BOX
SOFT SOLDER COMPOSITION :-3 PARTS LEAD,
3 PARTS TIN, 1 PART BISMUTH
1 *% . _ /* ?
'CJT^fe
9^
SOLDERING STRIP
'4 R fe
k x-*i
Fig. 6. Details of British Combination Fuse Cover and Case
tain if the defect is general. Should the fuses fail at this
further proof, the delivery will be rejected without refer-
ence to the original proof. The total proof of any delivery
shall not exceed 5 per cent of the lot. The contractor will
be required to replace all fuses expended in further proof or
examination free of charge, which, whether fired or other-
wise tested, will become the property of the government.
Inspection. (a) The components of the fuses, during
manufacture and assembling, and the completed fuses after
delivery, will be subject to examination and gaging by, and
274
BRITISH COMBINATION FUSE
to the final approval of, the chief inspector or an officer
deputed by him. Any component or fuse, which is not
finished to the satisfaction of the chief inspector, or his rep-
resentative, or which has any flaw or imperfection, will be
rejected.
(b) If, at any time during examination, it is found that
defects of any nature which involve rejection of the defec-
GBADUATION TABLE FOR TIME-RING ON BRITISH COMBINATION
TIME AND PERCUSSION FUSE
CROSS PAINTED RED
0.02 WIDE, 0.01 DEEP GROOVES
Graduation
Angle
Deg. Min
Graduation
Angle
Deg.
Min.
Oto5
Otol
Ito2
2 to 3
3 to 4
4 to 5
5 to 6
6 to 7
7 to 8
8 to 11 each
11 to 12
26
16
15
15
16
14
14
14
13
13
13
45
15
30
30
40
35
15
55
35
12 to 13
13 to 14
14 to 15
15 to 16
16 to 17
17 to 18
18 to 19
19 to 20
20 to 21
21 to 21. 2
13
13
12
12
12
11
13
14
16
3
10
50
30
30
10
30
20
30
tive components, or fuses, amount to 5 per cent of the num-
ber in the lot, the lot will be rejected.
(c) If, at any time during examination of the lot, it is
found that 5 per cent of fuses in the lot depart from the
approved design, further examination will be suspended.
The whole of the lot must be re-examined by the contractor
and those fuses which are incorrect to design eliminated.
Those fuses in which the departure can be rectified may
be changed to the approved design by the contractor. The
lot may then be re-submitted for examination.
BRITISH COMBINATION FUSE 275
Tests for Safety in Transportation. From each lot, 20
time and 20 percussion plungers are to be tested to ascer-
tain the correctness of their weights and static resistances.
Lots of plungers not correct within the tolerence allowed
will be rejected. At the commencement of manufacture, 6
time and 6 percussion plungers from each lot will be sub-
jected to a drop test against a steel block 11.5 inches in
diameter, 4.5 inches thick, resting on a concrete pier, to
determine the limit in heights at which the same will arm
when carried in standard dropping pieces. One of the
pieces weighs 15 pounds and has the form of a 3-inch shell ;
the two other pieces are lighter and smaller. No concus-
sion plunger is to begin to arm when falling in the lighter
piece from a height of 4 feet 6 inches; all shall fully arm
in the shell with 14 feet 8 inches drop. No percussion
plunger is to begin to arm in the special piece falling with
6 feet 2 inches drop; all shall fully arm in the shell with a
17 feet 6 inches drop.
Jumbling and Jolting Test. Ten fuses will be placed,
one at a time, in a wooden box approximately 16 inches by
11 inches by 5 inches inside dimensions, revolving at thirty
revolutions per minute, about one of its diagonals, for four
hours. The fuses will then be placed in an adjustable fuse-
holder on the end of a hinged lever 16 inches long, which,
by the motion of a cam, is raised 4 inches, thirty-five times
per minute, and allowed to drop on an iron anvil. The
fuses are thus dropped for an hour, point downward, base
downward, and side downward, respectively. The primer
shields must not be marked, and the time trains, powder pel-
lets, etc., must be intact.
CHAPTER XII
SPECIFICATIONS FOR BRITISH 18-POUNDER QUICK-
FIRING CARTRIDGE CASE AND PRIMER
The following specifications of the British 18-pounder
quick-firing cartridge case and primer govern the manu-
facture and inspection of these cases and primers. They
are abstracted from the official specifications and give the
most important information required by the manufacturer
and inspector.
Construction. The cartridge may be either solid drawn
brass or built up, the nature of the alloy and the thickness
and distribution of the metal being left to the contractor,
except that the dimensions must agree with those in Fig. 1.
The maximum weight is to be 3 pounds 1 ounce. If elec-
trolytic copper is used, it must be melted and run into
ingots before use. In manufacture the number of drawings
and the number of annealings must not be less than six.
Should any folds or rings exist in the metal of the base,
they must not be removed; any marks of cutting or turn-
ing of the metal of the inside of the base will cause the re-
jection of the cartridge. In the center of the base a hole is
to be bored and threaded to receive the primer. The cart-
ridges are to be marked on the base with the numeral and
the contractor's initials or recognized trade mark.
Screw Threads. The screw threads must, unless other-
wise stated, be of the standard Whitworth thread, be cut
full, and conform to the government inspector's standard
gages. Contractors may send their gages at any time to
the chief inspector to be checked and compared with the
standard gages.
General Conditions. The contractor is to supply, with
the first delivery, a full-sized tracing, on tracing cloth, of
the cartridge he is delivering. The contractor will also
supply, free of charge, samples of the metal from which the
cases are to be made, if requested by the chief inspector to
do so. The samples should not be less than 6 by 2 inches.
276
BRITISH CARTRIDGE CASE 277
Cases in stock, that is, cases made before the date of the
contract, must not be submitted for acceptance under a
given contract.
The cartridges should be delivered in lots of not less than
400. If less than 400 are delivered, the number of rounds
to be fired in proof will be the same as if the delivery were
the full 400. If, on examination of twenty per cent of a
lot, it is found that departures from approved design, or
defects of any nature, which involve rejection of the cases,
average twenty-five per cent of the number examined, the
whole of the lot will rejected.
Proof. (a) Not less than one-half per cent will be
fired in proof. At least one cartridge from each 400 de-
livered will be fired three times, one round being with a
proof charge, and the cartridge being (if necessary) re-
formed after each round. In each remaining cartridge, one
proof and one service round will be fired.
(b) The cartridge must load and extract easily, and
must not split or develop any flaw or crack on firing.
(c) The cartridge may be sectioned after firing; the
section must show no cracks.
(d) The maximum pressure is not to be more than 19
tons per square inch.
(e) If, in the proof of any delivery, defects appear
which involve the serviceability of the article, additional
proof may be taken from any other delivery not finally
closed, to ascertain if the defect is general or not. Should
the cases fail at this further proof, the delivery will be re-
jected without reference to the original proof. The total
proof of any delivery shall not exceed five per cent of the
number delivered.
Replacement of Proof. The contractor will be required
to replace all cartridges expended in proof free of charge,
and when the order is approaching completion, he will be
informed by the inspector how many are required to com-
plete the number on the order, exclusive of the cartridges
so expended, which, whether fired or otherwise tested, will
become the property of the government.
278
BRITISH CARTRIDGE CASE
Packing. All packages will be so marked that the goods
contained therein may be readily identified with the in-
voice. Unless specified herein that the packing cases or
other packing material will become the property of the war
department, they will remain the property of the contrac-
tor, who is responsible for their removal. Should they not
be removed within two months of the acceptance of the cart-
ridge cases, they will be disposed of, and in such circum-
stances the contractor will not be entitled to make any claim
^
~
I MIN. CAPACITY TO BASEJ
11 i OF PROJECTILE = 9+.8 Clj.lN.
' 8.25 -| Machinery
11
-i.o-
PARALLEL
Fig. 1.
British 18-pounder Quick-firing Cartridge Case, giving Complete
Dimensions, and Bore of Quick-firing Field Gun
for compensation. The packing cases must be marked "Re-
turnable" or "Non-returnable."
Spontaneous Cracking. Any cartridge found to be
cracked before or after filling, but before firing, is to be
replaced by the contractor if such crack is discovered within
six months of the date of acceptance of the cartridge in
question, which date is stamped on it.
The cartridges may be inspected during manufacture by,
and after delivery will be subjected to testing by, and to the
BRITISH CARTRIDGE CASE
279
final approval of, the chief inspector, Royal Arsenal, Wool-
wich, England, or an officer deputed by him.
Primer. The primer is to consist of the following parts
(see Fig. 2) : body A; closing disk B; anvil C; plug D; cap
E; tin foil F; ball G; paper disk H; gun powder /; and
Pettman cement. The body is to be made of composition
metal known as Class "A" or "B." All other metal parts
of the primer, except where otherwise specified, are to be
made of brass. The brass is not to contain more than 0.3
per cent of lead, nor to have more than one per cent of
total metallic impurities. The Class "A" or "B" metal is
to be in accordance with the following requirements: It
must be perfectly straight, uniform in diameter, and free
from cracks or flaws, and must be capable of standing the
following minimum tests:
Tenacity, Tons per
Square Inch
Elongation in Per Cent in such a Test
Piece as can be furnished, provided
that
Length
I/ 7 Area
Yield
Point
Breaking
Stress
Class "A", 20
Class "B", 12
Class "A", 30
Class "B", 20
Class "A", 20 per cent
Class "B", 30 per cent
Pieces of the metals it is proposed to use in the manu-
facture must be submitted free of charge by the contractor,
for testing, when requested by the chief inspector.
Body. The exterior of the body is to be turned and
threaded and a flange formed. Two slots are to be cut in
the head for the key. The interior is to be bored, cupped,
and threaded. The exterior of the body is to be lacquered
with a lacquer consisting of :
Seedlac 1 pound.
Turmeric 8 ounces.
Spirit, Methylated 8 pounds.
Screw, Plugs and Copper Ball. A plug having one end
turned to form an anvil, which is to be free from burrs, is
280
BRITISH CARTRIDGE CASE
-PAPER DISK SECURED WITH PETTMAN CEMENT
OUTSIDE TO BE COATED WITH A THIN LAYER
PAPER DISK SECURED WITH PETTMAN CEMENT
COATED WITH PETTMAN CEMENT UNDER TURNOVER
IF SAWED, NOT TO EXCEED 0.011
CLOSING DISK-BRASS
ANVIL- BRASS
Machinery
Fig. 2. Primer for British Quick-firing Shrapnel and High-explosive
Shell Cartridge Cases
BRITISH CARTRIDGE CASE 281
to be threaded to suit the body. The interior is to be turned
out to receive the soft copper ball, and three fire holes bored.
A plug is also to be threaded to suit the body, having an an-
nular recess turned on the inner side, and three fire holes
bored.
Cap. The cap is to be made of copper and the interior
is to be varnished with varnish composed of :
Finest orange shellac .... 2 pounds 2 ounces.
Spirit, Methylated 8 pounds.
The specific gravity of the varnish is to be 0.885. It is
then to be charged with 1.2 grain of the following compo-
sition (figures give parts by weight) :
Sulphide of antimony 18
Chlorate of potash 12
Ground glass 1
Meal powder 1
Sulphur 1
The composition is to be pressed into the cap with a
pressure of 800 pounds. A tin-foil disk, lacquered on one
side, is then to be placed on the composition with the lac-
quered side outwards, and placed under a pressure of 400
pounds. It is then to be varnished with a varnish com-
posed of:
Finest orange shellac .... 2 pounds 2 ounces.
Seedlac 1 pound.
Turmeric 8 ounces.
Spirit, Methylated 16 pounds.
The specific gravity of this varnish is to be 0.865.
The lacquer for the tin-foil disk before insertion is com-
posed of :
Seedlac 2 pounds.
Turmeric 1 pound.
Spirit, Methylated 16 pounds.
The specific gravity of this lacquer is 0.85.
The cap is to be externally coated with Pettman cement
before inserting in the body, and then a fillet of Pettman
282 BRITISH CARTRIDGE CASE
cement is formed between the body and cap; Pettman
cement is made from the following ingredients:
Gum shellac 7 pounds 8 ounces.
Spirit, Methylated 8 pounds.
Tar, Stockholm 5 pounds.
Red, Venetian 20 pounds 12 ounces
Gun Powder. The primer is to be filled with R. F. G. 2
powder, the screw plug being first screwed in and fixed
by three small punch blows, and the fire holes covered by a
disk of paper secured with Pettman cement.
Closing Disk. A brass disk having a paper disk se-
cured to it on the inner side by Pettman cement is to be
placed on the top of the powder, and a ring of Pettman
cement painted round the edge of the disk where the metal
will be burred over onto it. After the primer is burred over,
the whole of the exterior of the disk will also be coated with
a thin layer of the cement.
Marking and Delivery. The primers will be marked
with the numeral, serial number, contractor's initials or
recognized trade-mark, and date of manufacture. The
primers will be delivered in lots of 1000, an additional 20
being supplied for proof with each 1000, or any less num-
ber supplied. In the event of further proof being required,
the primers will be taken from the lot.
Proof. A percentage of the primers will be selected in-
discriminately for proof.
(a) The primer when screwed into a steel block must
fire correctly with a 1-pound weight falling 25 inches, and
ignite a puff consisting of 4 drams of R. F. G. ? powder
enclosed in one thickness of shalloon, in a 12-inch vent
with special receiver, or when proved in any gun for which
approved, it must ignite the charge without hang-fire.
(b) A miss-fire, hang-fire, pierced cap, or serious escape
of gas through or around the primer will cause rejection.
(c) The falling weight is to have a point of the same
shape as the service striker.
(d) Should the firing proof or examination of any de-
livery bring to notice any defect or defects which, in the
BRITISH CARTRIDGE CASE
283
[< eor
284 BRITISH CARTRIDGE CASE
opinion of the chief inspector, affect the serviceability of
the primers, the delivery in question may be rejected, or
further proof taken at his discretion, not only from the
particular delivery, but from any others made by the con-
tractor which may be under inspection, to ascertain whether
the defect is general. Should any primers fail at these fur-
ther proofs, the delivery or deliveries will be rejected with-
out reference to any previous proof.
If, on examination of twenty per cent of a lot, it is found
that departures from approved design or defects of any
nature which involve rejection of the defective primers
average 25 per cent of the number examined, the whole
of the lot will be rejected. The contractor will be required
to replace free of charge all primers expended in proof and
examination, which, whether fired or otherwise tested, will
become the property of the government.
Specifications for Cartridge Clip. The general dimen-
sions for the cartridge clip are given in Fig. 3. The clip
is made from hard-rolled sheet brass in one piece. Four
projecting arms are to be formed; the ends of each are bent
over as indicated. The clip is sand-blasted, and lacquered
with a lacquer composed of:
Vegetable black 1 pound.
Seedlac 1% pound.
Turpentine (1 quart) 2 pounds.
Methylated spirits (6 quarts) ... .12 pounds.
One arm is coated with paint consisting of:
Vermillion, dry 2 ounces.
Shellac, dry 1 ounce.
White hard varnish % ounce.
Spirits, Methylated l!/2 ounce.
Loop. The loop is to consist of 13 inches of "webbing,
cotton, 1/2 inch," threaded through the clip and sewed.
Three yards of webbing, selected from the bulk, are to be
submitted to the chief inspector before being used. The
webbing submitted will be cut into lengths of 11 inches and
the ends of each length securely fixed in the clamps of a
BRITISH CARTRIDGE CASE 285
testing machine, the clamps being 7 inches apart. The
strain will be gradually increased until the sample breaks.
The breaking strain must not be less than 200 pounds.
Delivery. The clips will be delivered in lots of 1000.
If, on examination of 20 per cent of a lot, it is found that
departures from approved design, or defects of any nature,
which involve rejection of the clips average 25 per cent of
the number examined, the whole of the lot will be rejected.
CHAPTER XIII
SPECIFICATIONS FOR AMERICAN SHRAPNEL SHELLS
The American shrapnel shells comprise the following
parts : forged shell body, copper driving band, head, washer,
tubes, bullets, matrix, head filler, diaphragm, base charge,
and fuse. In some cases a Semple tracer is used, and, when
this is the case, the base of the shrapnel must be machined
to accommodate it.
Shell. The shell is to be made of forged alloy steel or
bar stock having the properties outlined in Table I. The
forgings must be annealed so that they can be machined
with reasonable ease. The maximum elastic limit for the
2.95-inch and 3-inch shell forgings must not exceed 115,000
pounds per square inch, and in case of the 3.8-inch, 4.7-inch,
and 6-inch must not exceed 110,000 pounds per square inch.
All shrapnel shells must be subjected to an exterior hy-
draulic pressure of 20,000 pounds per square inch up to the
rotating band, and to an interior hydraulic pressure of 1000
pounds per square inch. A certain number from each 1000
shells are also subjected to- a ballistic test by firing com-
pleted shrapnels from a gun with a maximum pressure of
37,000 pounds, except for the 6-inch, which will be fired
under a pressure of 22,500 pounds per square inch.
The shell is to be finished outside and inside except at
points otherwise indicated, where it is to be left in the
rough-forged state. The inside of the shell is to be coated
with non-acid paint, except where machined, and the pow-
der chamber is to be given a heavy coat. Great care should
be taken to remove all burrs, scale, and sharp corners. The
outline of the shell after the first operation, when made
from bar stock, is shown by dotted lines in Fig. 1. The
base of the shell is to be machined as illustrated to the
right at A in Fig. 1, when a Semple tracer is used.
Copper Driving Band. The copper driving band is to be
cut from tubing of pure electrolytic copper, and machined
to the dimensions shown. It is to be heated and expanded
286
AMERICAN SHRAPNEL SHELL
287
PRESS METAL OF FUSE INTO
MATRIX
RESIN AND MONO-NITRONAPTHALENE
rW^-Si >< 0.45-~>t*-0.35-
MODIFICATION OF REAR END OF PROJECTILE
FOR USE IN 3 INCH HOWITZER
0.87
TUBE (A
ONE SEAMLESS DRAWN BRASS,
TUBING 0.05 THICK.
COAT INSIDE WITH SHELLAC
LOCKING PIN
TWO STEEL
FINISH 0.005
DRIVE AND PEEN AFTER
ASSEMBLING HEAD TO CASE
Fig. 1. Assembly and Details of American Shrapnel Shell
288
AMERICAN SHRAPNEL SHELL
to 2.985 inch inside diameter for the 3-inch shell and is
to be shrunk into the seat, then forced into the scores by
passing through a die and afterwards turned to size.
Washer and Head. The washer for the 3-inch shell-
is to be made from steel 0.031 inch thick and formed to
shape by punching. The head is to be made from cold-
drawn steel, finished all over, and coated inside with a non-
acid paint. The crimping wall is to be turned down over
FUSE HOLE PLUG
DIE CAST WHITE METAL
NON-CORROSIVE
0.010
FUSE HOLE PLUG
WROUGHT IRON OR BRONZE
0.010
0.03K
DIAPHRAGM
FORGED STEEL
0.005
.Machinery
Fig. 2. Details of American Shrapnel Shell
the washer after machining, and a hole drilled after the
head is assembled to the shell. Five notches equally spaced
are to be cut around the head, and a crimping groove cut
for putting on the fuse protecting cap.
Tube. The tube is to be made from seamless drawn
brass tubing, and is to be coated inside with shellac. An
additional short tube is to be inserted at the nose or mouth
of this tube, next to the fuse; this latter is to be made
from seamless drawn copper, and is to be forced into the
tube under pressure and crimped over.
AMERICAN SHRAPNEL SHELL
289
Bullets. The bullets used in the shrapnel are to be
made from 12.5 per cent antimony to 87.5 per cent lead,
and are to be flattened with six faces as shown in the illus-
tration ; 252 bullets are used in the 3-inch shrapnel.
Matrix and Head Filler. The matrix is to consist of
resin and mono-nitronaphthalene, poured into the shell, as
will be described in connection with loading. The head is
to be filled with melted resin, poured in.
Diaphragm. The diaphragm is to be made of forged
steel to the dimension shown. It is to be drilled and coun-
terbored, and great care should be taken to remove all burrs,
sharp corners, and scale. The bottom of the diaphragm is
also to be given a heavy coat of non-acid paint.
TABLE I. PHYSICAL PROPERTIES OF STEEL FOR VARIOUS
SIZES OF SHRAPNEL SHELLS
Caliber,
Inches
Tensile Strength,
Pounds
Per Square Inch
Elastic Limit,
Pounds
Per Square Inch
Elongation
in 2 Inches,
Per Cent
Contraction,
Per Cent
2.95
120,000
90,000
16
45
3.0
120,000
90,000
16
45
3.8
110,000
80,000
15
40
4.7
110,000
80,000
15
40
6.0
110,000
80,000
15
40
Fuse-hole Plug. There are two types of fuse-hole plugs ;
one is to be made from die-cast white metal, of non-corro-
sive properties, and machined to dimensions given in draw-
ing, and the other of wrought iron or bronze. The weight
of the wrought-iron plug for the 3-inch shell is to be
0.97 pound, and the weight of the bronze plug, 1.03 pound.
Either type of fuse-hole plug may be used.
Locking Pin. Two steel locking pins are required which
must be finished to limits of =t 0.005 inch, driven in and
peened over after the head is assembled in the shell.
Directions for Loading American 3-inch Shrapnel Shell.
In loading, make sure that the diaphragm seats firmly
on the shoulder in the shell, then pour in 0.25 ounce of pow-
dered resin to seal the joints, and shake down well to fill
all cracks. The powdered resin becomes plastic when the
290
AMERICAN SHRAPNEL SHELL
>l
O OOO
1
O
i O 1-1 <M CO
t- 1- t- t- 1-
00 J> IO OS
<N 04 CO T* 10'
<M O 10
(M 10 TH Or^
J> 00 O CO*
OS O 00 t- O
CQ CO CO ^ O
11
^2
CQ.r-i 1C O O5
<N <N <M CO CO
10
CO
o o o o o
iO IO O IO
00 l>
CO CO CO '^ ^O
CO <M CO
r* 00 ^^ CO CO
OS O 00 C- O
CO! CO* CO* rj<
AMERICAN SHRAPNEL SHELL
291
melted resin is poured in. Next put in one layer of bullets
(18) and pour in 0.4 ounce of melted resin; then put in 108
bullets and pack by a pressure of six tons. Then pour in
3.75 ounces of melted mono-nitronaphthalene ; put in 126
bullets ; drive down with mallet below end of tube ; and pour
in 4 ounces of melted resin. After the mass has thoroughly
cooled, face off matrix so that the depth from the end of
the shell shall be 0.27 inch to allow for screwing in head,
which should bear down hard on matrix. Next place washer
TABLE III. WEIGHTS AND MATERIALS USED IN AMERICAN
3-INCH SHRAPNEL SHELLS
Part
Material
Weight in Pounds
Shell
Steel
5.80
Driving Band
Copper
0.15
Washer
Steel
0.02
Head
Steel
0.45
Tube (including
inner tube)
Brass and Copper
0.09
Bullets (252)
Lead-antimony Alloy
6.05
Matrix
Resin and Mono-nitro-
naphthalene
0.52
Head Filler
Resin
0.03
Diaphragm
Steel
0.47
Base Charge
Shrapnel Powder
0.17
Fuse
1.25
Semple Tracer
0.20
Tracer Support
0.17
Total Weight
15.37 -+ 0.15
in head and secure it by turning down crimping wall. Then
fill annular space in lower face of head with melted resin,
and after this is thoroughly cooled, face off flush with lower
end of head. Screw head in place and secure with pins;
then insert inner tube, pour in the base charge through the
tube, and insert stopper. After the shell has been loaded,
the shell and head should be painted from the rotating bands
to the rear edge of the groove. For waterproofing, coat
with a pure raw linseed oil black paint. Coat the remain-
der of the head with bitumastic solution, and crimp the
waterproof cover in place while the solution is plastic. In
the lower end of the inner tube should be placed a stopper
of dry fibrous guncotton rolled tightly into a cylinder and
292
AMERICAN SHRAPNEL SHELL
pressed down until it rests on the shoulder of the diaphragm
and is about one inch long.
The case is to be stamped as follows with letters 1/16
inch high: Lot number of shrapnel shell, purchase order,
date of issue of purchase order, fiscal year, and initials of
manufacturer.
TABLE IV. PRINCIPAL DIMENSIONS OF VARIOUS SIZES OF CART-
RIDGE CASES USED ON AMERICAN SHRAPNEL SHELLS
ip-r 1 I I
4
i i
Machinery '
Dimensions in Inches
Caliber
in Inches
A B C D E
F
3.0 3.5 3.2 0.06 0.04 3.05
3.8 4.3 4.05 0.07 0.04 3.75
4.7 5.25 5.00 0.10 0.05 4.75
6.0 6.75 6.50 0.08 0.04 6.25
10.8
14.4
16.8
10.0
Cartridge Case. The various sizes of American cart-
ridge cases for shrapnel shells are drawn from a blank of
brass, known as "cartridge brass." The principal dimen-
sions of the various sizes of cases are given in Table IV.
The specifications covering the time and percussion fuse
used in American shrapnel shells are the same as for the
British "No. 85," given in Chapter XI, with the one excep-
tion that the base of the fuse body is shaped to suit the
American shell, and the thread is the U. S. standard, in-
stead of Whitworth standard.
INDEX
PAGE
American shrapnel shell, section of 3
specifications 286
American type of fuse 8
Annealing and washing cartridge cases 178
Automatic Machine Co.'s threading lathe used for threading shells 129
Band, machining rifling 68
pressing on rifling 66
Besly grinder equipped for grinding shrapnel 137
Brass for cartridge cases 235
Brass plugs for fuse, forging 145
Brass socket, machining 146
British cartridge cases, specifications 276
British fuses, specifications 260
British primers, specifications 279
British shrapnel shell, section of 3
specifications 251
Brown & Sharpe machines used for making fuse parts 164
Bullets, shrapnel 140
Caley method of making shrapnel forgings 20
Cartridge cases, annealing and washing 178
cupping 176
drawing 172
list of operations 190
machining 180
specifications for British 276
specifications for Russian 231
summary of operations 192
testing hardness of 179
Cartridge clip, British 284
Cleveland "Automatic" used for making shrapnel shells 85
Clip, British cartridge 284
Closing cap, machining 162
Closing screw, machining 162
Copper rifling band, machining 68
pressing on ! 66
Cupping cartridge cases 176
293
294 INDEX
PAGE
Detonators 15
specifications for Russian 245
Diaphragm forging ." 39
Drawing operations on cartridge cases 172
table of operations , 190
Drilling percussion primers 167
Drilling timing fuse plugs 170
Explosives, classification of 14
in shrapnel shells 4
manufacture of high 18
Forging brass plugs for fuse 145
Forging diaphragms 39
Forging fuse sockets 143
Forging shrapnel heads 38
Forging shrapnel shells 20
French shrapnel shell, section of 3
French type of fuse 11
Fulminates 15
Fuse, American type 8
French type 11
Russian type 9
specifications for British 260
specifications for Russian 213
time and percussion 6
Vickers' type 228
Fuse bodies, machining 150
Fuse hammers, making 165
Fuse nose, machining 156
Fuse nut, making 166
Fuse parts, making 143
Fuse plugs, drilling 170
Fuse sockets, forging 143
Fuse timing ring, graduating 171
Gages for shrapnel parts 72, 73
Gaging shrapnel shells 71
German shrapnel shell, section of 3
Graduating fuse timing ring 171
Gridley "Automatics," used for making fuse parts 156
used for making shrapnel shells 103
Grinding shrapnel shells 64, 132
Hardness testing, of cartridge cases 179
of shrapnel shells , 48
INDEX 295
PAGE
Head, machining shrapnel 152
Heading operations on cartridge cases, table 190
Heat-treating department, lay-out of . . 58, 59
Heat-treatment of shrapnel shells 47
Holinger method of making shrapnel f orgings 25
Hydraulic press method of forging shrapnel 29
Libby turret lathe used for machining shrapnel shells 122
Lo-swing lathe used for machining shells 114
Machines for shrapnel manufacture 75
Machining shrapnel shells 40
Marking shrapnel shells 74
New Britain "Automatics" used for making fuse, parts 146
Norton method of grinding shrapnel shells 133
Percussion primers, drilling 167
Potter & Johnston "Automatics" used for machining forged shells 90
Powder, black 15
smokeless 16
Powder cups, press tools for 139
Press tools for powder cup 139
Primers, charging 246
for fuses, drilling 167
specifications for British 279
Reed-Prentice equipment for machining shrapnel shells 75
Rifling band, machining. 68
pressing on 66
Rough-turning operations on shrapnel forgings 43
Russian cartridge cases, specifications for 231
Russian combination fuse, Vickers' type 228
Russian shrapnel shell fuses, specifications 213
Russian shrapnel shell, section of 3
specifications 194
Russian type of fuse 9
Shrapnel bullets 140
Shrapnel cartridge cases 172
Shrapnel head, forging 38
machining 152
Shrapnel shells, forging 20
grinding 64, 132
heat-treatment 47
296 INDEX
PAGE
history 1
machines and tools for manufacture 75
machining 40
present design 2
specifications for American 286
specifications for British 251
specifications for Russian 194
steel for 51
types 3
Smokeless powder 16
Socket, machining .146, 150
Specifications, for American shrapnel shells 286
for British cartridge cases 276
for British fuses 260
for British primers 279
for British shrapnel shells 251
for Russian cartridge cases 231
for Russian shrapnel shells 194
for Russian shrapnel shell fuses -. . . . 213
Steel for shrapnel 51
Tensile strength, testing 48
Testing hardness of cartridge cases 179
Testing shell body for hardness and tensile strength 48
Threading shells 129
Timing fuse plugs, drilling 170
Timing ring, graduating 171
machining 162
Tools for shrapnel manufacture 75
Varnish for cartridge cases. 242
Vickers' type of fuse 228
Warner & Swasey turret lathe, used for machining bar-stock
shells 112
used for machining forged shells 109
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