Improvements in Shot Cartridges.
Year: 1892

page_text: Date of Application, 8th Jan., 1892
Complete Specification Left, 7th Oct., 1892-Accepted, 12th Nov., 1892
PROVISIONAL SPECIFICATION.
Improvements in Shot Cartridges.
DANIEL LIST BRAIN (retired Lieut. Colonel) of Highfield, Ryde, I.W. do hereby
declare the nature of this invention to be as follows:-
The shot is contained in a case preferably of brass coil which is inserted on the
powder in an ordinary cartridge case. The case is thus designed. An inner
tube open at both ends forms the axis of case, or its interior. A cylinder, the
diameter of interior of cartridge, forms the exterior of case, between these cases
the shot is contained. The upper portion of the outer cylinder is divided into
equal & pointed segments, with slightly curved sides; to contain the shot these
segments are bent towards the upper end of inner cylinder, and their pointed
extremities bent over and folded into it. The shape of shot case then becoming a
cylinder with flattened conical head, the base being a circular rim connecting the
two cylinders. A modification might be made by introducing a spiral ridge in the
interior of the inner cylinder, that the force of discharge might give a rotating
movement to the shot case about its minor axis. That the gas might act on the
base of case & not escape through its axis, a cone can be inserted in central portion.
of powder wad with apex towards detonator.
Dated this 7th day of January 1892.
COMPLETE SPECIFICATION.
Improvements in Shot Cartridges.
DANIEL LIST BRAIN Lt. Col. of Highfield, Ryde, I.W. 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 my invention is to concentrate the shots or pellets of a charge fired
from the barrel of a smooth bore shot gun, not choked, so as to produce a closer
pattern, or a greater number of shot striking an objective of given area, at a greater
range than when the shots are placed loosely into a cartridge case.
The closeness of pellets during their flight giving also increased penetration.
To effect this I place the shot in a case, to be placed on the powder in a cartridge
case.
This shot case or container Fig. I. consists of an inner hollow cylindrical core (a)
forming its axis, and an outer case (b) of diameter equal to interior of cartridge
case. The core and outer case are joined at the base by an annular rim (b), on
which the shot rest. The forward part of the shot case is that of a truncated cone
or ogivale shape; thus formed. The outer case before being rolled round the base,
is serrated or divided in its front portion into Vandyck Fig. VI. salient & re-entering
angles from three to five divisions for convenience of filling with shot; the sides of
these projecting angular portions being curved so that when the pointed extremities
are bent towards the core and the points folded down into its interior Fig. I. the
case in its transverse sections is circular.
Fig. 11. shows the outer case open for filling.
Fig. III. gives projection of upper end of case when charged. In Figs. I. & IX.
(e) represents shot space.
The hollow core of case causes it during its flight to preserve the axis in the line.
of trajectory, as it thus presents the least resistance to the air, the greater area of
core for a given charge the less resistance.

page_text: On the discharge by force of explosive the greater momentum given to shot over
that of the case causes the folded in ends to be forced open, allowing the shot to
gradually escape during flight, but retaining them from a lateral divergence.
To cause the explosive force to act against the base of the charge, and not escape
as windage through the core, I form the wad over the powder of annular shape
corresponding to that of base of case, and in the central portion is inserted a cone
preferably of thin metallic foil with its apex towards the base of cartridge.
Fig. V. (d). This. cone also prevents a portion of the wad if of ordinary shape
being forced into the core and so present a resistance to the air. An alternative
device being a wad of hard material with a. central. plug fitting easily into the core.
The shot case is kept in the cartridge by a turn over. Fig. VIII. represents
section of cartridge fitted with described case & wad.
As a modification of the above smooth cylindrical core, and to give a rotation to
the shot case round its long axis to produce a greater range, I devise the two
following methods: The insertion of a thin flat band into the core, of width equal
to about half its diameter, to which is given a half or entire twist in its length.
Or again the formation of the core itself in a spiral, with threads three or more in
number, according to diameter of core and size of shot, with a half or entire twist
for its length.
Fig. VII. shews a core so formed of four threads and spiral of one half twist.
The re-entering portions of screw.between the threads being preferably arcs corre-
sponding to circumference of shots used.
Fig. VII. shews a section of screw core with grooves each. a quadrant of circum-
ference of shot. On projecting of the case, the shot traversing. the grooves before
escaping, would give a rotation or spin to the case.
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. A case of form and construction as herein described, to contain a charge of
shot, to be placed in a cartridge.
2. A central core for aforesaid shot case, of screw shape to cause it to rotate or
spin during its flight round its long axis, as herein described.
3. The insertion of a twisted band into this core, to cause the case to rotate in
like manner.
4. A wad of design herein described to be used between this shot case and the
explosive, in a cartridge case.
Dated this 5th day of October 1892.