Improvements in or relating to Cartridges.
Year: 1893

page_text: Date of Application, 25th Jan., 1893
Complete Specification Left, 25th Oct., 1893-Accepted, 2nd Dec., 1893
PROVISIONAL SPECIFICATION.
Improvements in or relating to Cartridges.
A communication from ULDARIQUE Marga, of 57, Rue St. Georges, Brussels, in
the Kingdom of Belgium, Captain.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I. Mech. E., and Chartered Patent Agent, do hereby declare the nature of this
invention to be as follows:-
The object of the improved cartridge for fire-arms, described in a previous
Patent of my correspondent, was to obtain, in comparison to ordinary cartridges,
and assuming the charge of powder to be the same, less internal pressure, greater
initial speed in the flight of the projectile, and a greater force of penetration of the
latter. These results however paradoxical they may appear at first sight, have
been over and over again confirmed by experiment according to this invention.
They are obtained owing to the fact that the combustion or deflagration of the
charge in the improved cartridge is "differential " i.e. takes place in parts or
fractions instead of being simultaneous as in ordinary cartridges. The advantages
of the former mode of combustion will be clearly apparent from the comparative
examination of the two methods.
The
In an ordinary cartridge the whole charge is converted into gas at once.
maximum pressure of this gas is very high and therefore dangerous, while it acts
both upon the breech of the fire-arm and the projectile or bullet before it sets the
latter in motion, but the moment when the projectile begins to advance within the
barrel the space within the fire-arm increases and the pressure of the gas, rapidly
expanding in such space as the projectile moves forward, goes on decreasing until
the projectile leaves the barrel. Thus the pressure exercised upon the projectile,
although very considerable at the moment of the deflagration, acts with a steadily
decreasing force as the bullet travels from the breech to the barrel. Now it is by
this gradually decreasing propelling power that the initial speed of the bullet 13
determined and this fact has a most disadvantageous influence upon the force of
penetration of the projectile.
If instead of progressively decreasing, the pressure, acting upon the projectile, as
it travels from one end of the barrel to the other, were uniform, it will be understood
that the initial impulse given to the bullet as it leaves the barrel, would also be
constant and normal, being free from the weakening effect of the diminishing
pressure, and therefore naturally its force of penetration would be materially
enhanced.
To obtain this result the deflagration is so differentiated or divided that in the
first place one part of the charge causes the projectile to advance within the barrel
thereby producing an increase of space for the gases generated by the remaining
portion of the charge to expand in. While this pressure will therefore be com-
paratively low, it will be uniform and of greater useful effect than the gradually
diminishing pressure which has been hitherto produced; so that the initial speed is
imparted to the projectile under far more favourable conditions than before, both
the speed and the force of penetration of the bullet being increased without the
necessity of creating even momentarily any of those enormous pressures which have
up to the present time been resorted to. Besides if necessary the deflagration of the
charge may be so differentiated that the pressure in the barrel instead of remaining
constant, increases and gives a more and more powerful impulse to the bullet as it
approaches the orifice of the fire-arm.
Such division of the deflagration which as has been just explained may vary

page_text: according to requirements, is obtained by dividing the charge into fractions and it
may moreover be assisted by the employment of powder specially prepared for
gradual or differential combustion.
In order to cause the projectile to issue from the fire-arm under a constant
pressure it is sufficient to divide the charge of homogeneous powder contained in
the cartridge into two portions. The cartridge is for this purpose constructed
differently from those now in use. It mainly consists of two concentric cases or
tubes the inner of which constitutes the cartridge proper as it contains the
fulminate cap, while the external tube or case simply serves as a reservoir for the
powder. These two cases are only in so far connected with each other that they
are jointly or simultaneously closed by the projectile, the. centre of which covers
the mouth of the inner case, while it is firmly set or fitted within the contracted
circular edge of the external case in the ordinary manner, as has been described
already in the previous Patent above referred to.
It will be readily understood that when a double cartridge such as this is fired,
the powder contained in the central case being first ignited, starts the projectile,
or gives it the first impulse, then, while it is in motion, it receives the supplemental
impulse from the charge contained in the external case or reservoir, which has in
the meantime commenced to burn. In this manner the whole of the gases due to
the total effect of the deflagration of the two charges is evenly and uniformly
divided throughout the length of the barrel, and therefore during the whole time
that the projectile travels from one end of the barrel to the other and also at the
moment when it leaves the barrel, it moves under the maximum impact obtainable
in a given space and under given circumstances, for the development of such force
of impact takes place from the first throughout the whole space available, and
therefore the projectile is fired by this powerful initial force and not by a pressure
constantly and rapidly decreasing as the said projectile moves.
If it be desired to obtain a gradually increasing pressure, there may be placed
immediately underneath the bullet, in addition to the ordinary charge, a block of
compressed powder or say pyroxyline, which being ignited at the same time as the
rest of the charge, will burn while the bullet is advancing within the barrel,
thereby constantly increasing the density of the gases until the bullet issues from
the gun.
Some of the arrangements which may be employed to carry out in practice the
above principles and various modifications of the mode of attachment of the central
or internal case to the bottom of the outer case or powder-reservoir are as follows,-
the purpose of all these being to obtain an absolutely hermetic closing of the two
parts so as to obviate any possible escape of gas at the back of the cartridge.
Each cartridge consists of the projectile or bullet, the powder reservoir or
external case, the central or internal case or tube and the fulminate cap with its
anvil. In the first form the bottom of the reservoir may have a conical aperture
into which is fitted a trumpet-shaped piece which terminates the internal tube and
receives the fulminate cap of corresponding shape which in its turn receives the
anvil. All these parts are fitted together at one stroke in a suitable press or
machine.
In a second form the perforation in the bottom of the cartridge is differential in
diameter, the inner tube being contracted near its lower end so that the piece here
assumes a cylindrical shape. Within the contraction is located the upper edge of a
cylindrical cap inserted by means of a press and as it were hooked on to or suspended
from the inner tube by means of its inwardly projecting annular flange which is
retained in the groove formed by the offset of the tube and the end-piece of that
tube. The anvil in this case forms part of the cap which also contains the fulminate,
the whole forming the complete cap.
In a third modification the cylindrical piece also forming the end of the tube
receives the fulminate cap with its anvil which in this case is independent of it.
It rests directly upon the bottom of the cap which as in the preceding arrangement
is hooked on to or retained by the end piece.

page_text: In another modification the end piece of the inner tube being contracted at its
base, itself forms the anvil while the cap containing the fulminate is as before retained
in place by its annular flange.
A fifth modification consists in forming the central tube with an end piece closed
at the bottom. The fulminate-cap is in this case inserted into the inner tube (along
with its anvil) through the top of the said tube.
The case is slightly reduced in diameter immediately above the end-piece so as
to retain cap and all at the bottom of the cartridge where it has been introduced by
means of a suitable press.
An arrangement for connecting the internal tube with the powder-reservoir
which is so strong as to stand any test and prevent any possible recoil of the central
tube, when for unforeseen reasons the projectile sustains a shock, may be as follows,-
the central tube is doubly supported by the bottom of the cartridge, being retained
in both directions by a flange on each side of the annular projection. This arrange-
ment is carried out in practice in the following manner. The internal tube the
diameter of which corresponds to that of the central opening of the projecting or
contracting part is provided at its back end with a flange abutting against the lower
side of the said projecting part when it is inserted into the cartridge. In this
position, a suitable mandrel is introduced into the tube through the lower end. The
whole is then placed in a press which holds the flange at the same time as it causes
the mandrel to advance within the tube which is thereby slightly widened until the
mandrel arrives at the projecting portion, which thus forms as it were a second
seat for the tube. In this manner the tube grasps the combination of parts
on all sides so that they cannot be displaced whatever the strain they may be
subjected to.
According to one arrangement the anvil is integral with the edge while in the
other the anvil is inserted separately, whereby the strength of the attachment of the
tube is still further increased. When the tube and its parts are all fitted in place,
the fulminate cap is forced over the anvil through the bottom of the cartridge in
the ordinary manner.
In order to interpose an extra charge of compressed powder or pyroxyline
between the bullet and inner case, when it is desired to gradually increase the
pressure acting upon the bullet in firing, a cylindrical or slightly conical block may
preferably be employed. This block is perforated in its axis and slides upon a tube
the lower closed end of which is fitted within the central tube so that the base of
the block rests upon the edge of the central tube thereby covering the ordinary
charge, while its upper end is embedded in the bottom surface of the bullet, slightly
recessed for the purpose.
If there be any reason to fear lest the total combustion of the block shall not be
completed in the space of time allowed for this, such combustion may be accelerated
by causing the said block to be ignited simultaneously at both ends. In this case
the tube T may remain open at the base, and a firing pin or piston may readily be
applied, which closes the tube at its base and is retained in position by a spiral
spring located between it and a double hole, provided at the upper part of the tube
and containing a priming of fulminate. The fire is thus distributed through lateral
ports and ignites the top part of the block of pyroxyline under the action of the
said firing piston driven forward by the deflagration of the charge of the inner tube
simultaneously igniting the lower part of that block, which being thus fired at both
ends at the same time is of course much more quickly consumed.
Dated this 25th day of January 1893
W. P. THOMPSON & BOULT,
Of London, Liverpool, Nottingham, and Manchester,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Cartridges.
A communication from ULDARIQUE MARGA, of 57, Rue St. Georges, Brussels, in
the Kingdom of Belgium, Captain.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
The object of the improved cartridge for fire-arnis, described in a previous Patent
of my correspondent, was to obtain, in comparison to ordinary cartridges, and
assuming the charge of powder to be the same, less internal pressure, greater initial
velocity in the flight of the projectile, and a greater force of penetration of the
latter. These results however paradoxical they may appear at first sight, have
been over and over again confirmed by experience, according to this invention.
They are obtained owing to the fact that the combustion or deflagration of the
charge in the improved cartridge is "differential" i.e., takes place in parts or
fractions instead of being simultaneous as in ordinary cartridges. The advantages
of the former mode of combustion will be clearly apparent from the comparative
examination of the two methods.
The
In an ordinary cartridge the whole charge is converted into gas at once.
maximum pressure of this gas is very high and therefore dangerous, while it acts
both upon the breech of the fire-arm and the projectile or bullet before it sets the
latter in motion, but at the moment when the projectile begins to advance within
the barrel the space within the fire-arm increases and the pressure of the gas,
rapidly expanding in such space as the projectile moves forward, goes on decreasing
until the projectile leaves the barrel. Thus the pressure exercised upon the pro-
jectile although very considerable at the moment of the deflagration acts with a
steadily decreasing force as the bullet travels from the breech to the muzzle. Now
it is by this gradually decreasing propelling power that the initial velocity of the
bullet is determined and this fact has a most disadvantageous influence upon the
force of penetration of the projectile.
If instead of progressively decreasing, the pressure, acting upon the projectile, as
it travels from one end of the barrel to the other, were uniform, it will be under-
stood that the initial impulse given to the bullet as it leaves the barrel, would also
be constant and normal, being free from the weakening effect of the diminishing
pressure, and therefore naturally its force of penetration would be materially
enhanced.
To obtain this result the deflagration is so differentiated or divided that in the
first place one part of the charge causes the projectile to advance within the barrel
thereby producing an increase of space for the gases generated by the remaining
portion of the charge to expand in. While this pressure will therefore be com-
paratively low, it will be uniform and of greater useful effect than the gradually
diminishing pressure which has been hitherto produced so that the initial speed is
imparted to the projectile under far more favourable conditions than before, both
the initial velocity and the force of penetration of the bullet being increased
without the necessity of creating even momentarily any of those enormous pressures
which have up to the present time been unavoidable. Besides if necessary the
deflagration of the charge may be so differentiated that the pressure in the barrel
instead of remaining constant, increases and gives a more and more powerful
impulse to the bullet as it approaches the muzzle of the fire-arm.
Such division of the deflagration which as has been just explained may vary
according to requirements, is obtained by dividing the charge into fractions and

page_text: it may moreover be assisted by the employment of powder specially prepared for
gradual or differential combustion.
In order to cause the projectile to issue from the fire-arm under a constant
pressure it is sufficient to divide the charge of homogeneous powder contained in
the cartridge into two portions. The cartridge is for this purpose constructed
differently from those now in use. It mainly consists of two concentric cases or
tubes the inner of which constitutes the cartridge proper as it contains the fulminate
cap with its anvil, while the external tube or case simply serves as a reservoir for
the powder. These two cases are only in so far connected with each other that
they are jointly or simultaneously closed by the projectile the centre of which covers
the mouth of the inner case, while it is firmly set or fitted within the contracted
circular edge of the external case in the ordinary manner, as has been described
already in the previous Patent above referred to.
It will be readily understood that when a double cartridge such as this is fired,
the powder contained in the central case being first ignited, starts the projectile,
or gives it the first impulse, then, while it is in motion, it receives the supple-
mental impulse from the charge contained in the external case or reservoir, which
has in the meantime exploded. In this manner the whole of the gases due to the
total effect of the deflagration of the two charges is evenly and uniformly exerted
throughout the length of the barrel, and therefore during the whole time that the
projectile travels from one end of the barrel to the other and also at the moment
when it leaves the barrel, it moves under the maximum impulse obtainable in a
giveu space and under given circumstances, for the development of such force takes
place from the first throughout the whole space available, and therefore the pro-
jectile is fired by this powerful initial force and not by a pressure constantly and
rapidly decreasing as the said projectile moves.
If it be desired to obtain a gradually increasing pressure there may be placed
immediately underneath the bullet, in addition to the ordinary charge, a block of
compressed powder, such as pyroxyline, which being ignited at the same time as
the rest of the charge, will burn while the bullet is advancing within the barrel,
thereby constantly increasing the density of the gases until the bullet issues from
the gun.
Some of the arrangements which may be employed in practice in conformity with
the above principles are shown in the accompanying drawings, which illustrate the
improved Marga cartridge, with various modifications of the mode of attachment
of the central or internal case to the breech-end of the outer case or powder-
reservoir, and are as follows the purpose of all these being to obtain an
absolutely hermetic union of the two parts so as to obviate any possible escape of
gas at the back of the cartridge.
Each cartridge consists (as shown in all the figures) of the projectile or bullet P,
the powder reservoir or external case R, the central or internal case or tube D
and the fulminate cap C with its anvil E. In the first form (Figure 1) the breech-
end of the powder chamber or reservoir R may have a conical aperture into which
is fitted a trumpet or bell-mouthed annex p which terminates the internal case D
and receives the fulminate cap C of corresponding shape, together with the anvil E.
All these parts are fitted together at one stroke in a suitable machine-press.
In a second form (Figure 2) the perforation in the breech-end of the cartridge
is differential in diameter, the inner case D being contracted near its lower end so
that the annex p here assumes a cylindrical shape. Within the contraction is
located the upper edge of a cylindrical cap C' inserted by the machine-press and
as it were hooked on to or suspended from the inner case D by means of its inwardly
projecting annular flange which is retained in the groove formed by the offset of
the case and the end-piece or annex p thereof. The auvil in this case forms part
of the cap C' which together with the fulminate forms the complete cap C.
In another modification (Figure 3) the cylindrical annex p forming the end of
the case D receives the fulminate cap C with its anvil E, which in this case is

page_text: independent of it. Both rest directly upon the bottom of the cap C' which as in.
the preceding arrangement is hooked on to or suspended from the annex p.
In a third modification (Figure 4) the end-piece or annex p of the inner case D
being cone-shaped at its base, itself forms the anvil E, while the cap C containing
the fulminate retains it in place by the annular flange-suspension as before.
A fourth modification (Figure 5) consists in forming the central case D with its
annex p closed at the bottom and containing the fulminate-cap C with its anvil E,
which, in this instance, is inserted through the open end of the central case D,
which is then compressed so as to be slightly reduced in diameter immediately
above the annex p in order to retain the fulminate-cap the whole being sub-
sequenty fixed in the breech-end of the outer cartridge-case by a stroke of the
machine-press.
An arrangement, for connecting the internal case D with the powder-reservoir R,
which is so strong as to stand any test and prevent any possible recoil of the central
case D when from unforeseen causes the projectile sustains a shock is shown in
Figures 6 and 7, and may be as follows:-the central case D has a double bearing
on the breech-end of the cartridge, being retained in both directions by a shoulder
above and below an annular boss or projection on the breech-end. This
arrangement is carried out in practice in the following manner. The internal
case D the diameter of which corresponds to that of the central opening of the boss
or projection O is expanded below the boss, at the other end of the said opening, so
as to form a flange abutting against the lower side of the said projection when it
is inserted at the breech-end of the cartridge. In this position, a suitable mandrel
is introduced into the inner case D through its upper or open end. The whole is
then placed in a press which holds the flange at the same time as it causes the
mandrel to advance within the tube which is thereby slightly enlarged until the
mandrel arrives at the boss or projection at the breech-end of the outer case R,
which thus forms as it were a second bearing for the inner case D. In this manner
the latter grasps the projection so firmly on all sides of the opening that it cannot
be displaced whatever the strain it may be subjected to.
""
20
According to one arrangement (Figure 6) the anvil is formed integral with the
flange or collar while in the other (Figure 7) the anvil is inserted separately in
the machine-press, whereby the firm attachment of the inner case D is still further
strengthened. When the parts are all fitted in place, the fulminate cap C is
forced over the anvil E through the bottom of the cartridge in the ordinary
manner.
In order to interpose an appropriate charge of compressed powder or pyroxyline
between the bullet and inner case, when it is desired to gradually increase the
pressure acting upon the bullet in firing, a cylindrical or slightly conical block of
powder may preferably be employed. This block is perforated in its axis and
slides upon a tube T the lower closed end of which is fitted within the central
internal case D so that the base of the block rests upon the edge of the case thereby
covering the ordinary powder-charge, while its upper end is embedded in the
bottom surface of the bullet, slightly hollowed for the purpose.
If there be any reason to fear lest the total combustion of the block shall not be
completed in the space of time allowed for this, such combustion may be accelerated
by causing the said block to be ignited simultaneously at both ends. For this
purpose the tube T may remain open at the base, and a firing pin or piston-striker
may readily be applied, which closes the tube at its base and is retained in position
by a spiral spring located between it and a double bottom, provided at the upper
part of the tube forming a cavity containing a priming of fulminate. The fire is
thus distributed through lateral ports and ignites the top part of the block of
pyroxyline under the action of the said firing-piston driven forward by the
deflagration of the charge of the inner case simultaneously igniting the lower part
of that block which being thus ignited at both ends at the same time is of course
much more quickly consumed.

page_text: Having now particularly described and ascertained the nature of this said inven-
on as communicated to me by my foreign correspondent, and in what manner the
ame is to be performed, I declare that what I claim is :-
1. A differential-fire cartridge for fire-arms whereof the characteristic is the
actional subdivision of the charge in such manner that a small portion only
ereof, enclosed in a central case or chamber D drives the projectile forward into
e bore thus creating a considerable space for the expansion of the gases generated
y the deflagration of the bulk of the charge contained in the powder-chamber or
uter cartridge-case R whereby the violent initial pressures exerted on the breech
y the simultaneous deflagration of the entire charge are avoided a greater initial
elocity is imparted to the projectile and a greater penetrative power is obtained
e effects of this improvement admitting of being increased by a further
ifferentiation of the charge by the aid of portions of powder of greater density
bstantially as described.
2. Fixing the interior central case D within the powder-chamber R of the
artridge by :-
:-
a. Terminating the breech-end of the inner central case D with a trumpet or
bell-mouth p, cone-jointed to the breech-end of the powder-chamber or outer
case R the insertion therein of a fulminate-cap of similar shape all these
parts being fitted together by a single stroke of a suitable machine-press, as
in Figure 1; or in a modification by contracting the said end of the case D
in the form of an annular groove from which the cylindrical cap containing
the fulminate and anvil is held by its internal edge being bent inwards to
engage with said annular groove by the same stroke of the press that fits the
parts together as in Figure 2; or in a third modification, by a somewhat
similar suspension of the said cap Cover the enlarged cylindrical end p of
the inner case D, containing an independent cap C as in Figure 3; or again
as in the modification shown by Figure 4 wherein the enlarged cylindrical
end P of the inner case D terminates in a cone forming also the anvil enclosed
in the suspended cap C¹ containing the fulminate.
b. The construction of the inner case D with a closed annex p and subsequent
insertion of the cap, with fulminate and anvil by ulterior contraction of the
case above the annex p as shown in Figure 5.
c. The insertion of the inner case D in a central boss or projection O formed
in the breech-end of the outer cartridge-case being firmly held therein,
firstly, by the terminal flange or collar r and secondly by the shoulder
formed by the enlarged diameter of the front portion of the case D the
anvil E being either formed in one piece with the flange or separately
inserted and the whole being enclosed or headed in by the fulminate cap,
substantially as described and illustrated.
3. The use in certain proportions of gunpowders of greater density such as
roxyline in compressed blocks the arrangement of such block between the internal
se D and the projectile P on a tube T passing axially through the block, and
ally the application and use of a special striker or hammer within the said tube T
th the object of effecting the simultaneous deflagration of the anterior and
sterior portions of the compressed powder-block substantially as described and
r the purposes specified.
Dated this 24th day of October 1893.
W. P. THOMPSON & BOULT,
Agents for the Applicant.