IMPROVE- MENTS IN CARTRIDGES FOR ORDNANCE & SMALL ARMS
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
I DAVID FITZGERALD DOWNING Captain in the Royal Artillery of Woolwich in
the County of Kent do hereby declare the nature of my invention for IMPROVE-
MENTS IN CARTRIDGES FOR ORDNANCE & SMALL ARMS to be as follows:-
I press the explosive into the form of a solid cartridge or cartridges of about the
same diameter as the chamber of the gun, cylindrical in form & slightly coned-the
interior being pierced by one or more longitudinal holes & the exterior covered by
a suitable envelope to prevent ignition taking place from the exterior-The ignition
takes place from the interior holes & the production of gas is increasing from the
first. The density of the explosion may be advantageously arranged by pressing
mandrils through the holes.
COMPLETE SPECIFICATION.
I DAVID FITZGERALD DOWNING Captain in the Royal Artillery stationed at
Woolwich in the County of Kent do Ecreby declare the nature of my invention
for IMPROVEMENTS IN CARTRIDGES FOR ORDNANCE & SMALL ARMS and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
I employ an explosive compressed into one solid mass having at the same time
one or more longitudinal perforations through it, from the surfaces of which the
burning commenses & spreads outwards, so that the generation of gas may be con-
tinually increasing as the explosion progresses, & the pressure on the base of the
projectile thus maintained as it passes down the bore of the gun.

page_text: This action is ensured as follows. The exterior of the explosive is protected
from ignition by a tightly fitting envelope which prevents the access of the heated
gases to this part. The breaking up of the explosive mass is prevented by support
being given to the exterior of the envelope or case by the powder chamber from
the first in order to ensure this the powder chamber is coned & the exterior of
the cartridge similarly coned to fit it-means being provided to ensure close
contact before firing-This means may consist of a compressible base giving it's
own obturation as in Fig. 1., or of a spring bearing against the obturator of the
gun when the breech is closed as in Fig. 2.-if in the latter case more than one
cartridge constitutes the charge the spring of one would bear against the face of
the next, the strength of spring varying with the position of the cartridge.
Fig. 1. shows a section of a small arms cartridge (with one central perforation in
the explosive) in which the base is made separate from the body & connected to it
by a throat on the body swedged into an undercut recess in the base-The body is
formed with a flange for the extractor to engage & between this & the base lies a
wad of asbestos-the face of the base is carved so that the breech block in closing
may press against it-the closing of the breech therefore presses the cartridge
home into it's seat in the powder chamber, play being allowed by the compressi-
bility of the wad & the undercut recess. The wad helps to seal the escape-of-gas.-
The base being separato from the body facilitates the pressing in of the explosive.
Fig. 2. is a section of a cartridge (with one central perforation in the explosive)
more suited to ordnance. In this the pressing home of the cartridge is effected by
a spiral spring- which bears against a thrust frame attached to the base of the
cartridge. The casing of the cartridge is made of incombustible- material &
exteriorily coned to fit the powder chamber similarly coned-grummets of asbestos
or other suitable material are attached to facilitate handling & extraction-Both
ends may be protected-by-thrust-frames which_bear against the casing to prevent
injury to the explosive block in these parts.
In all cases the means for ensuring the cartridge being pressed home before firing
may be attached to, & so form part of the gun, the object to be attained remaining
the same.
In order to give stiffness & afford a grip for the explosive, so that it
may preserve it's contact & formn, & also to facilitate extraction, the casing may be
fluted longitudinally or circumferentially.
Having now particularly described & ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
1. Cartridges in which the explosive is pressed into one solid mass having
however one or more longitudinal perforations, & enclosed in a. tightly fitting
envelope, the exterior of the envelope or outer casing being coned to fit the
chamber of the gun similarly coned, & means being provided to ensure contact
between cartridge & chamber before tiring.
2. Cartridges having coned exteriors & fluted longitudinally or circumferentially
substantially for any of the purposes described.
Dish: De
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