Year: 1894

page_text: Date of Application, 24th Feb., 1894
Complete Specification Left, 24th Nov., 1894-Accepted, 29th Dec., 1894
I, HIRAM STEVENS MAXIM, of Baldwyn's Park, Bexley, in the County of
Kent, Mechanical Engineer, do hereby declare the nature of this invention to be
as follows:-
This invention relates to cartridges and has for its object to obviate the injurious
scouring action of the powder gases on the barrel of the rifle or gun. My said
improved cartridge is more especially intended for use with smokeless powder, but
it may be used with ordinary powder.
With cartridges constructed as heretofore, especially when used with smokeless
powder, there is great liability of the gases to escape around the rear end of the
bullet or projectile between the projectile and the barrel of the weapon thereby
setting up a very severe scouring action on the barrel, and more especially in the
rifling thereof, besides resulting in a considerable loss of propelling power. The
barrel is by this action very quickly destroyed, it being able to withstand possibly.
about 600 rounds; but in many cases not more than 300 rounds can be fired before
the barrel is destroyed. The chief cause of the escape of the powder gases in the
manner above indicated is the rigidity of the rear end of the hard metal casing
which surrounds the lead part of the bullet, such rigidity being mainly due to the
turning or flanging inward of the rear end of said case over the end of the bullet.
This rigid corner resists the pressure of the gases and is not driven sufficiently deep
into the rifling to completely block the passage around the bullet.
n
In my said improved cartridge I provide a hard case which takes the rifling, in
combination with a lead portion to effect the obturation. This combination
constitutes the chief novel feature of my invention.
In carrying my invention into effect according to a preferred construction I
make the hard metal case or envelope of the projectile. somewhat shorter than
the lead portion thereof, and I form the rear end of said case with a sharp
bevelled or feather edge, and preferably also I make the rear face of the bullet
slightly hollow.
The case or envelope aforesaid is secured to the bullet by a circumferential
channel or cannelure formed near the rear end thereof, which is sunk into the lead,
and locks the two parts securely together. The rear projecting part of the lead
is made flush with the outer diameter of the case. The projectile so made is
passed into the forward end of the cartridge case and is held therein by forcing the
metal of the cartridge case into the cannelure before mentioned.
When the cartridge is fired, the part of the envelope of the projectile imme-
diately forward of the cannelure takes the rifling and ensures the proper rotation of
the projectile, while the lead base is driven outward to fill the rifling completely,
thereby effectually preventing any escape of powder gas and obviating erosion of
the barrel.
In a modification of my invention I make and secure the projectile case as
heretofore but I provide therein a large number of radial holes preferably arranged
in zig-zag lines, which holes I fill with lead. At the moment of firing, the lead is
forced out of said holes into the rifling of the barrel and effectually prevents the
escape of the powder gases.
According to another modification I fill the cannelure in the projectile envelope
with lead and I provide a number of holes through said cannelure forming a

page_text: communication between the lead inside the case and the lead in the cannelure
These holes are filled with lead. By this means I provide for performing the
obturation at the moment of firing.
In both the last named constructions the lead does not need to project rearwardly
beyond the envelope.
If so desired, the lead may be hardened by the addition thereto of a smal
percentage of antimony or tin.
Dated this 24th day of February 1894.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents:for the Applicant.
I, HIRAM STEVENS. MAXIM, of Baldwyn's Park, Bexley, in the County of
Kent, Mechanical Engineer, 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:--
With cartridges having bullets or projectiles encased in hard metal and
constructed as heretofore, there is great liability of the powder gases to pass
between the projectile and the barrel of the weapon. This passage of the gases
produces a very severe scouring action on the rifling, and causes a considerable loss
of propelling power. Moreover, the barrel is thereby very quickly destroyed, in
many cases three hundred rounds being sufficient to render it unserviceable so. far
as accurate shooting: is concerned. The escape of the powder gases past the bullet
is chiefly due to the rigidity of the rear end of the hard metal envelope which
surrounds the lead. filling of the bullet in such a manner as to resist the expansion
of the base of the bullet and prevent the spreading of the latter sufficiently to
properly fill the rifling and thus completely effect the obturation. The rigidity of
the base of the bullet is mainly due to the inward turning or flanging of the rear
end of the hard metal envelope over the end of the lead part of the bullet.
The scouring is more severe when the cartridge is charged with smokeless
powder than when it is charged with ordinary powder, and my improved cartridges
are more especially intended for use with charges of smokeless powder, though they
may be advantageously used with charges of ordinary powder.
My invention has for its object the prevention of the aforesaid scouring action
and the consequent rapid destruction of the gun barrel.
According to my invention I make a bullet or projectile with a hard metal
envelope (preferably the usual alloy of nickel and copper) that takes the rifling
and contains a soft lead core which is so. formed and combined with the.envelope
and with the cartridge case that it will act to insure the obturation as hereinafter
set forth!
Referring to the accompanying drawings,
Figure 1 ista side, view of a cartridge constructed according to my invention, the
bullet or projectile and a portion of the forward end of. the cartridge case being
shown in longitudinal central section.
Figure 2 is a side elevation, and
Figure 3 is a longitudinal central section of a modified: construction of projectile
made according to my invention.
Figure 4 is a longitudinal central section of another modified form of projectile.
A is the cartridge case; B is the projectile or bullet consisting of a hard
metallic envelope b and a core or filling of lead b'; C is the charge of powder.
In the construction shown in. Figure 1 the hard metal envelope b is.shorter than
the lead part 6 the rear end of which projects from the envelope b and fits the

page_text: interior of the cartridge case A... Preferably the rear end of the bullet is made
hollow. The rear end of the envelope b is bevelled or reduced to a knife edge as
shown at b³.
A cannelure or circumferential channel is formed in the envelope b at 6* by
pressing the bard metal into the lead and so locking the two parts of the bullet.
together. The bullet so made is then passed into the case A and is retained therein
by forcing the metal of the case at D into the cannelure b³.
When the cartridge is fired, the part of the envelope b immediately forward of
the cannelure 6 takes the rifling and ensures the proper rotation of the projectile,
while the projecting lead base is driven outward first against the interior of the
case A and then against the barrel and fills the rifling completely thus effectively
preventing any escape of powder gases and obviating erosion of the barrel.
In the modification of my invention shown in Figures 2 and 3, I provide the
envelope b near the rear end thereof with a number of holes & preferably arranged
in zig-zag lines; these holes are filled by the lead b¹.
At the moment of firing the gun, the lead is forced out through the holes b*
into the rifling of the barrel and effectually prevents the escape of the powder
gases.
According to the further modification illustrated in Figure 4 I fill the cannelure 6*
with lead, and I provide a number of holes 6 through the cannelure to form a
communication between the lead inside the envelope and that in the cannelure.
These holes are also filled with lead. The obturation is performed at the instant
of firing by the lead which is forced outward through the holes 6*.
In both of the modifications above described, the lead b' does not need to project
rearwardly beyond the end of the envelope b.
The lead may be hardened if desired by the addition thereto of a small per-
centage of antimony or tin.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The bullet or projectile having a hard metal envelope and a soft lead core
or filling, so constructed at the rear end or the part within the cartridge case that
the soft lead will expand and fill the rifling of the barrel immediately after the
firing of the gun, for the purpose specified.
2. A bullet or projectile constructed substantially as described with reference
to Figure 1 or to either of the modifications shown in Figures 2, 3 or 4, for the
purpose specified.
3. A cartridge which has a bullet or projectile constructed and combined with
the case substantially as described with reference to the accompanying drawings,
for the purpose specified.
Dated this 24th day of November 1894.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.