SPECIFICATIONS FOR THE MANUFACTURE AND INSPECTION OF THE RUSSIAN 3-INCH
SHRAPNEL SHELL
[Illustration: Fig. 1. Russian 3-inch Shrapnel Shell and Component
Parts]
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 consists 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 accordance 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 manufacturing the same have not been altered. Firms
are allowed to begin the manufacture of the shells before delivering
the test consignment, but on the condition that in the case of
unsatisfactory results of the trials of the test consignment, 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 ascertaining 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 testing machine. In the case of the last three
shells it is necessary to ascertain before cutting the test pieces
from them that the driving bands are pressed on correctly, by removing
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 mentioned tests may be carried out only if the metal
shows results 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 immediately 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 recovered 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 rejection 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 increase 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 allowed 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 satisfactory
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.
=Clause 3. Breaking Tests of the Material used for Bodies.=--These
tests must be carried out at the works where shrapnels 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 considered
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 addition 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 shrapnels 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 assembling, and
pit tests.
The whole order is sub-divided into consignments of 5000 shrapnels
each. The method of manufacture of the shrapnels 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
consignment, and must form a separate proof consignment when it is more
than half of same.
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 prevent any
further submission of same for proof. The shrapnels 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 rejected 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 mechanical tests of the
metal must be carried out by the inspector 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 exception 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 consignment 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.
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 shrapnels
must be subjected to the same test, but for the acceptance 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 during 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 secondary, the
permission for the further manufacture of projectiles 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 looking 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.
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 shrapnels submitted for acceptance, and he
has the right to suggest improvements to the manufacturer; it is left
to the discretion 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 manufactured the
works must pass them by their own examiners; these examiners must work
to the instructions given to them by the works, and prepared to the
inspector’s satisfaction. 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 finished; 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 centering 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 portion of the body against the diaphragm must be properly
finished; the upper part of the inside surface must be provided 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 center 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 outer surfaces of the central portion and
the enlarged centering 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 dimensions 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 consignment, 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 copper, not drawn, must not be used for
driving bands. The copper strips must be cut into pieces of the lengths
required 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 until the ends
meet; when the ends meet, the strip is hammered 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.
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 returned to the firm
for reviewing. If during secondary examination 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 mandrel 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
requirements. 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 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 driving bands, in order to ascertain how close they
are to the shrapnel bodies. The inspector also has the right to demand
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 unsatisfactory, 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 are submitted 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 submitted with them
for the first inspection. The powder chamber, lower portion of steel
diaphragms, and inner surface 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 allowed 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.
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 ascertain the following
facts:
1. If the powder chamber, lower surface of steel diaphragms, and inner
surface of the central tube are varnished; 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 contact 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.=--Diaphragms 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 diaphragm, 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 hammering them by
the dropping of a weight from a certain height. The number of blows
which the diaphragms can stand without any cracks must be ascertained
by the inspector 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 diaphragms will be chosen
by the inspector from the total number 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 number 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 ⁵⁄₈ inch in length (1¹⁄₂ 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 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 being
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 accurately 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 hammering 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 machined, 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. Shrapnel 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, except 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 bullets 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 filling with resin and for the escape of gases must
be stopped 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 inspected and gaged. After this
inspection the shrapnels are weighed. The shells which show the ends of
the driving bands not completely touching each other, may be accepted
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 dismantling 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 shrapnels are
filled with smoke composition.
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 varnished. This nickel-plating and
varnishing must be durable. 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 manufacturer
after being nickel-plated so as to ascertain that no liquid passed
inside the powder chamber, and, if necessary, 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 driving bands must be gaged during this inspection.
While inspecting the shrapnels, the inspector must see to the following
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.
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 being damaged by knocks
from the outside, or from rattling one against the other, or against
the packing during transport.
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 supplied, 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 carried out with steel or brass dummy
fuses similar to those used for accuracy trials. These dummy fuses must
be supplied 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 explodes. 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 the shrapnels proved for recovery must be fired with bursting
charge, so as to ascertain that they are properly assembled. 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 measuring 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 expense. 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 shrapnels 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.