Improvements in Cartridges for Guns of Large Calibre.
Year: 1889

page_text: Date of Application, 7th Jan., 1889
Complete Specification Left, 3rd Oct., 1889-Accepted, 30th Nov., 1889: .
PROVISIONAL SPECIFICATION.
Improvements in Cartridges for Guns of Large Calibre.
}
I, THORSTEN NORDENFELT of 53 Parliament Street in the City of Westminster,
Civil Engineer, do hereby declare the nature of this invention to be as follows:-
The object of this invention is to provide metallic cartridges for guns of large calibre
and such as can be made at a more moderate cost than the metallic cartridges at
present in use.
I enclose the powder charge in a cylindrical or somewhat conical casing of thin brass
or other metal either drawn solid or brazed and I provide metal ends to this casing.
The ends are soldered or otherwise fixed in place so as hermetically to close the casing.
At the base end of the casing and in the centre thereof the metal is so thin than it can
easily be perforated.
In the sides of the casing on the exterior there are four or other number of
longitudinal grooves; they are equally spaced around the casing; the purpose which
they serve is explained further on. The rear part of this casing is fitted into a base
cup which is stamped or cast in bronze or other meta!. The base cup is of the
form usually given to the base end of a metallic cartridge or it differs therefrom
but slightly. When it is in its place and supported by the breech block it closes the
breech of the barrel gas tight. The hollow in the front face of the cup is cylindrical,
slightly grooved at the sides to ensure extraction, and the base of the casing con-
taining the charge fits into it. Four or other number of stays, preferably oval in
section are riveted into the bottom of the base cap they are equally spaced around the
interior of the cup against the side. These stays pass through holes in the bottom and
are secured on the outer side by rivetting. The stays pass along the case containing
the powder charge and they occupy the longitudinal grooves provided in its exterior.
The stays terminate in heads of a hook like form which overlap the outer end of the
charge case and so serve to hold it in its place within the base cup. The heads of
the stays are perforated and a copper wire serves to tie them together over the end of
the charge case.
In the bottom of the base cup on the outer side there is a central recess to
receive a primer preferably removable. The primer consists of a percussion cap and a
cap chamber.
The cap chamber is conical in its general form; it is hollow and
perforated at its apex; the cap fits within it and when exploded by the firing
mechanism of the gun the flash from it passes through the perforation and reaches
the charge.
The cap chamber is flangel around its base and the flange is turned over around
its edges into a cylindrical form. The exterior of this cylinder fits within the cavity
in the outer side of the base cup whilst its interior fits over a nipple left standing
within the cavity. The head of the nipple is somewhat wider cut and the flange by
its elasticity springs in around it and grips it so that when the cap chamber is pushed
into its place it becomes securely attached to the base cup of the cartridge.
increase the elasticity of the flange of the cap chamber radial slits are formed
in it.
To
The point of the cap chamber through which the passage is formed for the fire from
the cap to reach the charge is sufficiently strong and sharp to perforate the thin
metal in the centre of the base of the casing containing the charge and it does thus
perforate it when the cap chamber is thrust into its cavity so that when the
cartridge is fired the flash from the cap reaches the charge without impediment.
Datul this 5th day of January 1880

page_text: COMPLETE SPECIFICATION.
Improvements in Cartridges for Guns of Large Calibre.
I, THORSTEN NORDENFELT of 53, Parliament Street in the City of Westminster,
Civil 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 :-
The object of this Invention is to provide metallic cartridges for guns of large
calibre and such as can be made at a more moderate cost than the metallic cartridges
at present in use.
I enclose the powder charge in a cylindrical or somewhat conical casing of thin
brass or other metal either drawn solid or brazed and I provide metal ends to this
casing. The ends are soldered or otherwise fixed in place so as hermetically to close
the casing. At the base end of the casing and in the centre thereof the metal is so
thin that it can easily be perforated.
In the sides of the casing on the exterior there are four or other number of
longitudinal grooves, they are equally spaced around the casing, the purpose which
they serve is explained further on. The rear part of this casing is fitted into a base
cup which is stamped or cast in bronze or other metal. The base cup is of the form
usually given to the base and of a metallic cartridge or it differs therefrom but slightly.
When it is in its place and supported by the breech block it closes the breech of the
barrel gas tight. The hollow in the front face of the cup is cylindrical, slightly
grooved at the sides to ensure extraction, and the base of the casing containing the
charge fits into it.
Four or other number of stays, preferably oval in section are
riveted into the bottom of the base cup, they are equally spaced around the interior of
the cup against the side. These stays pass through holes in the bottom and are
secured on the outer side by rivetting. The stays pass along the case containing the
powder charge and they occupy the longitudinal grooves provided in its exterior.
The stays terminate in heads of a hook like form which overlap the outer end of the
charge case and so serve to hold it in its place within the base cup. The heads of the
stays are perforated and a copper wire serves to tie them together over the end of
the charge case.
In the bottom of the base cup on the outer side there is a central recess to receive
a primer preferably removable. The primer consists of a percussion cap and a cap
chamber. The cap chamber is conical in its general form; it is hollow and perforated
at its apex the cap fits within it and when exploded by the firing mechanism of
the gun the flash from it passes through the perforation and reaches the charge.
The cap chamber is flanged around its base and the flange is turned over around
its edges into a cylindrical form. The exterior of this cylinder fits within the
cavity in the outer side of the base cup whilst its interior fits over a nipple left
standing within the cavity. The head of the nipple is somewhat under cut and the
flange by its elasticity springs in around it and grips it so that when the cap
chamber is pushed into its place it becomes securely attached to the base cup of the
cartridge. To increase the elasticity of the flange of the cap chamber radial slits
are formed in it.
The point of the cap chamber through which the passage is formed for the fire
from the cap to reach the charge is sufficiently strong and sharp to perforate the
thin metal in the centre of the base of the casing containing the charge and it
does thus perforate it when the cap chamber is thrust into its cavity so that
when the cartridge is fired the flash from the cap reaches the charge without
impediment.
In order that my said Invention may be fully understood and readily carried
into effect will proceed to describe the drawings hereunto annexed.
DESADIDITION OF THE DRAWINGS

page_text: Figure 3 is a longitudinal section, and
Figure 4 is a transverse section of a cartridge constructed in accordance with my
Invention.
Figures 5, 6, 7 and 8 are similar views of another cartridge also constructed in
accordance with my Invention.
Figure 9 shows separately one of the longitudinal stays of the latter
cartridge.
In Figures 1, 2, 3 and 4a is the cylindrical or somewhat conical body of the
powder case, it is closed in front by the end piece a¹ and in rear by the
piece a².
The end piece has a hole at the centre and this is closed by a thin disc of
soft. metal which is readily perforated. Ai a* a* are longitudinal grooves in the
sides of the powder case, is the base cup into which the rear end of the powder
case fits.
cecare iron stays, three are shown in the drawing, riveted into the base
cup and occupying the grooves a* their ends d' overlap the end a¹ of the powder
case and retain the cast a in place. is a copper wire which ties the ends of the
stays together.
The description above applies also to the cartridge shown by the figures 4 to 8 except
that in this cartridge the stays are made so thin that it is not necessary to groove.
the cartridge case to receive them. These flat stays are riveted by rivets of to the sides
of the cup b.
Holes are formed in the stays into which the walls of the case a are
bulged when the cartridge is fired so that the stays obtain a sufficient hold of the case
to ensure extraction.
(see Figure 3) is a cavity in the bottom of the base cup to receive the
primer (see Figure 7) is a groove formed around the cavity leaving between the
two a nipple with an under cut head. The cap chamber fits into the cavity and over
the head of the nipple. e' is the conical point of the cap chamber which perforates
the disc a³ and which has a passage through it for the flash of the cap to pass to the
charge. 2 is the part of the cap chamber which fits the cavity is the flange
projecting from the part e; at its outer edge it is itself turned up into a cylindrical
Form. This part has slits cut in it so as to leave four little tongues sufficiently
elastic to spring inwards when the cap chamber is put into its place and embrace the
under cut head of the nipple with sufficient firmness to prevent all danger of the cap
chamber falling out from its place at the base of the cartridge. The cap consists of
two parts, the capf (properly so called) which contains the fulminate and the perforated
anvil piece g. The cap fits into the anvil piece g and this in turn fits within the
cap chamber as the drawing shows.
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 means of connecting the powder case and the base cup by longitudinal stays
substantially as described.
2. Cartridges substantially as described and represented by the annexed
drawings.
3. The means of attaching the cap chamber to the base cup by clipping springs
the former embracing a nipple formed upon the latter substantially as
described.
on
4. The combination substantially as described consisting of the metallic powder case
so formed at its rear end as to admit of easy perforation; the detachable base cup;
and the cap chamber fitting a recess in the base cup and so formed that when the
parts are brought together the cap chamber penetrates the base of the powder case
as herein set forth.
Dated this 27th day of September 1889.