Improvements in the Manufacture of Metallic Cartridge Cases.
Year: 1892

page_text: Date of Application, 20th July, 1892
Complete Specification Left, 10th Apr., 1893-Accepted, 27th May, 1893
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Metallic Cartridge Cases.
I HENRI SCHNEIDER of Le Creusot in the Republic of France Manufacturer
do hereby declare the nature of my said invention to be as follows:-
This invention relating to the manufacture of metallic cartridge cases is more
particularly applicable to cases for cartridges for use in quick firing guns.
The cases of cartridges for quick firing guns consist of a tube of suitable length
closed at one extremity; they require to be of great strength in order to ensure
perfect freedom from leakage or escape of gas in firing. These cases may be made
either in one piece by a stamping and drawing process or in a number of parts
joined together such parts usually consisting of a tube and a base piece.
Cases obtained by a stamping and drawing process are extremely difficult to
manufacture and when they are of considerable length and frequently present
irregularities with regard to the strength of their base the metal having been
compressed or upset at this part by a long series of operations by which it is
strained and weakened. The body of the case is also more difficult to manufacture
when in place of being a plain tube it is required to have one extremity closed and
of considerable thickness.
With the object of obtaining cases presenting greater regularity and greater
strength I make them in two parts namely a tube and a base piece connected
together by a gas tight joint of peculiar form as hereinafter described.
The tubular part of the cartridge case is constructed with an enlargement or
thickening at the rear end in which is formed a screw thread and a plain or
unthreaded cylindrical extension of smaller diameter.
The principal parts of the base piece are as follows:-
1. A threaded part acting as a nut being screwed on to the threaded part of
the tube.
2. An annular groove for the reception of the plain or unthreaded extension of
the tube.
3. An internal flange or annular projection which is carefully fitted into the end
of the tube into which it enters for a certain distance.
By these means the tube is firmly connected to the base its extremity or
unthreaded extension being inserted into the recess and being overlapped internally
by the flange on the base piece. This peculiar method of connecting the parts by
screwing insertion and overlapping at the joint ensures perfect freedom from leakage
in firing. The gases resulting from the explosion cannot pass between the surfaces
of the joint as their pressure acting on the internal flange on the base tends to
expand this flange and press it with great force against the extremity of the tube.
Dated this 20th day of July 1892.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Metallic Cartridge Cases.
1, HENRI SCHNEIDER of Le Creusot in the Republic of France Manufacturer
do hereby declare the nature of my invention and in what manner the same is to
performed to be particularly described and ascertained in and by the following
statement:-
.
This invention relating to the manufacture of metallic cartridges cases is more
particularly applicable to cases for cartridges for use in quick firing guns.

page_text: .
The cases of, cartridges for quick firing guns consist of a tube of suitable length
closed at one extremity, they require to be of great strength in order to ensure
perfect freedom from leakage or escape of gas in firing. These cases may be made
either in one piece by a stamping and drawing process or in a number of parts
joined together such parts usually consisting of a tube and a base piece.
Cases obtained by a stamping and drawing process are extremely difficult to
manufacture especially when they are of considerable length and frequently present
irregularities with regard to the strength of their base the metal having been
compressed or upset at this part by a long series of operations by which it is
strained and weakened. The body of the case is also more difficult to manufacture
when in place of being a plain tube it is required to have one extremity closed and
of considerable thickness.
With the object of obtaining cases presenting greater regularity and greater
strength I make them in two parts namely a tube and a base piece. connected
together by a gas tight joint of peculiar form as hereinafter described.
And in order that my said invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 of the accompanying drawings represents in section a cartridge case
according to this invention and Figures 2 and 3 drawn to a larger scale illustrate
in section details of the base piece and tube respectively.
The tubular part (marked A in the drawing) of the cartridge case is constructed
with an enlargement or thickening A' at the rear end in which is formed a screw
thread d and a plain or unthreaded cylindrical extension e of smaller diameter.
The principal parts of the base piece (marked B in the drawing) are as
follows:-
1. A threaded part a acting as a nut being screwed on to the threaded part d of
the tube.
2. An annular groove b for the reception of the plain or unthreaded extension e
of the tube.
3. An internal flange or annular projection e which is carefully fitted into the
end of the tube into which it enters for a certain distance.
By these means the tube is firmly connected to the base its extremity or
unthreaded extension e being inserted into the recess and being overlapped
internally by the flange c on the base piece. This peculiar method of connecting
the parts by screwing, insertion and overlapping at the joint ensures perfect freedom
from leakage in firing. The gases resulting from the explosion cannot pass between
the surfaces of the joint as their pressure acting on the internal flange con the base
tends to expand this flange and press it with great force against the extremity of
the tube.
The tubes which should be made with great care are preferably tested by
internal pressure for the purpose of discovering any flaws that may exist. in the
metal.
The base pieces are preferably cut out of a metal of suitable strength so as to be
in no way deteriorated by machining or preparatory processes.
I do not.limit myself as to the dimensions of the parts or as to the nature of
the metals employed.
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 manufacture of metallic cartridge cases composed of a tube and a base
piece connected together by a screw and by the combination of a recess such as b
and an overlapping projection such as c in such a manner as to form a gas tight
joint between the parts when firing substantially as hereinbefore described with
reference to the accompanying drawings.

page_text: 2. The arrangement and combination of parts constituting the improvements
in the manufacture of metallic cartridge cases substantially as hereinbefore
described.
Dated thin 10th
C
A 1 1000
J. H. JOHNSON & Co.,
Agents.