Improvements in Projectiles for Ordnance.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Projectiles for Ordnance.
I, HIRAM STEVENS MAXIM, of 18, Queen's Gate Place, in the County of
Middlesex, Chevalier of the Legion of Honour, Civil and Mechanical Engineer,
do hereby declare the nature of this invention to be as follows:-
-
This invention has reference to projectiles of the kind referred to in the
Specification of my prior l'atent No. 28093 of 1896 in which a flexible metallic
cap or disc having a peripheral rim or flange is provided at the base of the pro-
jectile for compressing an obturating ring or gas check when the pressure of
the powder gases acts upon the said cap or disc.
The chief feature of my present invention consists in forming the aforesaid
disc and its peripheral flange in two parts instead of in one piece as heretofore
such parts being subsequently connected together in any appropriate manner.
In carrying my invention into practice I provide a ring preferably of mild
steel which is adapted to fit around a shoulder at the base of the projectile, the
said ring having an annular recess in its outer edge to receive the bent peripheral
edge of the flexible disc which is preferably formed to tough rolled steel. When
the said ring and disc have been fitted to each other they are subjected to
hydraulic or other pressure to cause them to remain permanently fixed together.
The said outer edge of the mild steel ring is advantageously curved to more or
less conform to the curved shape of the portion of the disc adjacent thereto, so
that when said disc is bent or deformed by the pressure of the powder gases, it
will not meet any sharp corners on the said ring. The said outer edge of the
ring may also be enlarged to make it of greater area than that of the inner
edge, in which case it would be found desirable to recess the base of the projectile
for the said enlarged portion of the ring to enter, so that the movement of said
ring would not be impeded when subjected to the pressure of the powder gases.
The plastic obturating ring would be situated between the inner edge of the
said ring and the aforesaid shoulder on the base of the projectile, so as to be
compressed by the movement or deformation of said ring as is well understood.
Dated this 8th day of August 1899.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: 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:―
This invention, has reference to projectiles of the kind referred to in the
Specification of my prior Patent No. 28093 A.D. 1896 in which a flexible metallic
cap or disc having a peripheral rim or flange is provided at the base of the pro-
jectile for compressing an obturating ring or gas-check, when the pressure of
the powder gases acts upon the said flexible metallic cap or disc.
It has hitherto been usual to obtain the aforesaid peripheral flange by dishing
or bending the cap or base-piece near its edge, but when thus formed the base-
piece when subjected to the gas pressure has been liable to fracture at the part
adjacent to the bend, with the result that the pressure of the powder gases has
not been transmitted to the gas-check in an efficient manner. It is the object
of my invention to overcome this liability by forming the aforesaid flexible cap
or base-piece and its peripheral flange in two parts instead of in one piece as
heretofore, that is to say I substitute for the said flange a stout ring made
separately and subsequently connected to the base-piece in any appropriate
manner.
In order that my said invention may be clearly understood and readily carried
into effect, I will now proceed to describe the same more fully with reference to
the accompanying drawings, in which:
Figures 1 and 2 are longitudinal sections of the rear portion of a projectile
provided with my improved cap or base-piece; Figure 1 representing the parts
approximately in the position they occupy prior to the firing of the gun and
Figure representing the said parts approximately in the position they occupy
after firing and when the flexible base-piece has been acted upon by the pressure
of the powder gases.
2
A is the projectile body; B the flexible base-piece; C the ring which serves as
the flange thereof; 1) the screw for securing the base-piece to the projectile; E
the gas-check; F the driving band, and G the gun barrel.
The ring C, as already stated is a stout ring made preferably of mild steel and
adapted to fit around a shoulder a formed at the base of the projectile, the said
ring having an annular channel or recess c in its outer or rear face to receive the
peripheral edge 6 of the base-piece. The said base-piece is preferably made of
tough rolled steel. When the said ring C and the base-piece B have been fitted
to each other, they are subjected to hydraulic or other pressure to cause them to
remain permanently united. The outer face of the ring C is curved at the part c¹
to more or less conform to the curved shape of the portion of the base-piece
adjacent thereto, so that when said base-piece is bent or deformed by the pressure
of the powder gases, it will not meet any sharp corners on the said ring that
would tend to fracture it. The said outer face of the ring C is also preferably
enlarged so that its surface is of greater area than that of the inner face. The
base of the projectile is also recessed at a¹ for the said enlarged portion of the
ring to enter, so that the forward movement of said ring will not be impeded
when the pressure of the powder gases acts upon it and the base-piece.
The gas-check E is composed of a substance which I term semi-plastic such
as that, for example, referred to in the Specifications of my former Letters Patent
No. 680 of 1890 and No. 28093 of 1896 and is situated between the inner face of
the said ring C and the base of the projectile as shewn, so as to be compressed
by the movement of said ring C.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim in projectiles for ordnance is:-
1. A flexible base-piece provided with a ring applied thereto substantially as
and for the purpose specified.

page_text: 2. The construction of the said ring with a curved portion c¹ substantially as
and for the purpose specified.
3. A projectile having its base-piece and ring constructed and arranged sub-
stantially as described with reference to the accompanying drawings for the
purpose specified.
Dated this 17th day of January 1900.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.