IMPROVEMENTS IN PROJECTILES
Year: 1855

page_text: LETTERS PATENT to Andrew Hotchkiss, of the City of New York, United
States of America, for the Invention of "IMPROVEMENTS IN PROJECTILES."
Sealed the 14th August 1855, and dated the 5th March 1855.
PROVISIONAL SPECIFICATION left by the said Andrew Hotchkiss at the
Office of the Commissioners of Patents, with his Petition, on the 5th
March 1855.
I, ANDREW HOTCHKISS, of the City of New York, United States of America,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
PROJECTILES" to be as follows:-
This Invention consists in the formation of shot or shells capable of being
fired from a rifled cannon, and producing the same effect as slugging the
balls in breech-loading guns, and similar small arms. The shot is made in
the general form known by the term "conical ball," and as shewn in the
annexed Drawing at A. The point, if made as a hollow shot, may have
a nipple cast to receive a percussion cap. The novel feature consists in
casting around the back end a soft metal ring, say of lead, as shown at b.
It is intended that this ring shall be expanded by the act of firing, and be
forced against the sides of the bore and also into the grooves, and thus not
only enable the shot to receive the action of the twist, but shall also pack the
shot piston-like in the gun to avoid windage. This result is produced by a cap
of hard metal, which fits over the end of the shot, but inside of the ring of lead,
as shewn at c.
It will be seen that the metal cap is bevilled at the sides, so that compressing

page_text: the shot and the cap together produces the expansion of the edge of the ring.
In loading, therefore, the rammer on sending home the ball effects the expan-
sion of the ring in the first instance by forcing the cap into the lead, and this
is still further and more effectually accomplished by the concussion produced
by the act of firing.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Andrew Hotchkiss in the Great Seal Patent Office on the
23rd August 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ANDREW
HOTCHKISS, of the City of New York, United States of America, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of March, in the year of our Lord
One thousand eight hundred and fifty-five, in the eighteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Andrew Hotchkiss, Her special licence that I, the said Andrew Hotchkiss, my
executors, administrators, and assigns, or such others as I, the said Andrew
Hotchkiss, my executors, adininistrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN PROJECTILES,"
upon the condition (amongst others) that I, the said Andrew Hotchkiss,
by an instrument in writing under my hand and seal, should particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
"
NOW KNOW YE, that I, the said Andrew Hotchkiss, do hereby declare the
nature of my said Invention, and in what manner the saine is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, reference being had to the Drawings hereunto annexed,
that is to say :--
My Invention is for certain improvements in projectiles for ordnance, and
consists in a method of constructing a cast-iron shot so that it shall be capable
of being fired from rifled cannons, and also shall have effects similar to the
slugging of balls in breech-loading guns. The shot is made in three distinct
parts, two of said parts being of cast iron or similar metal, and the third of

page_text: some softer and more flexible material, such, for instance, as lead, the whole
when combined together forming to external appearance an egg-shaped shot.
The construction and operation are as follows:-The body of the shot consists
of a casting having one end formed into a blunted point, similar to the usual
conical ball, as seen at A, Fig. I. The opposite end of this body from a little
beyond the middle tapers off into a tail-piece, seen at B, and is also squared
at the end. Upon each corner of the square the metal is, cut away a little, so
as to form a projection, shown at the letter (c), the object of which will be
explained further on. About the middle of the body A, two recesses are
formed completely around, as at (E) and (E), thus leaving a projection (i)
between. Upon these the lead ring is cast, and the recesses and projection
serve to keep it on. This ring is at C, part being shown in section. From
the point at (E) it will be seen that the inner surface is chamfered off, as
shown, and leaves a cup-shaped termination. The second casting will now be
described. This consists of a cap, which is to enclose the tail-piece B, and is
to effect the expansion of the projecting edge of the lead ring into the grooves
of the cannon. It is shown at E, Fig. I., with a view looking directly into
the interior in Fig. II. The rim of this cap is chamfered or bevelled off
from the outside, as shown in the sectional part at (o), and where it will ba
seen to fit in and press upon the like bevelled edge of the leaden ring.. In the
head of the cap inside is a projecting ring (8), through which four notches (81)
are cut, as shown in Fig. II., and these permit the projections (c) to pass
through. The object of this will now be made apparent, for by turning the cap
slightly round the projections pass by the notches and become locked by the
solid part of the ring, and thus the parts A and E are held together. In order
that the cap may expand the leaden ring it must have play upon the tail B, for
which it will be seen there is room left in the cavity (t) beyond. The tail acts
also as a guide to the cap, insuring a direct forward motion, since without such
guide the cap might be driven a little out of the true line, and the result would
be that the ring, being more expanded on one side than on the other, would cause
windage on that other side, and consequently destroy the accuracy of the fire.
The effects in the act of firing are as follows:-The bore of the cannon must
be spirally grooved, on a principle similar to that of a rifle. The flat part of
the ring C should fit the smooth part or "lands" of the bore. In sending it
down, the flexible ring may be slightly expanded by a blow of the rammer as
soon as the shot is home. It is in the act of firing, however, that the ring C is
expanded, so as to take a full impression of the grooves; for by the force with
which the cap E is driven toward the body of the shot or A, and before
momentum is communicated to the latter, the lead ring will be expanded, that

page_text: being the point of least resistance, and be thereby caused to take the impression
of the grooves, as also to be packed tightly against the rest of the chamber.
This prevents windage, and of course insures the full effect of the powder, while
at the same time rotary motion is imparted to the shot. The flexible ring also
has this important advantage, that it does not wear or damage the grooves of
the gun even in case of "stripping," should such action occur, and hence there
is no reason why the wear should not be as long as in the plain bore.
What I claim as of my Invention is,―
Firstly, constructing a shot or projectile capable of being fired from a cannon
having rifle grooves, said shot consisting of three parts, two of which parts are
of hard metal, and the other of some flexible expansive material in the form of
a band or ring attached to one of the hard metal parts, and overlapping the
edge of the other in such manner that either by the act of loading or of firing,
or of both, the said ring shall be so expanded or distended that it shall take the
impression of the grooves, and be made to fit the bore, as described.
Secondly, I claim the tail-piece for securing the cap to the body of the shot,
and as a guide to the cap in its forward motion, in the manner described.
In witness whereof, I, the said Andrew Hotchkiss, have hereunto set
my hand and seal, this First day of June, A.D. One thousand eight
hundred and fifty-five.
ANDREW HOTCHKISS. (L.S.)
Taken and declared at Her Britannick Majesty's
Consulate, City of New York, this 15th day of
June 1855, before me,
(L.S.)
ANTII. BARCLAY,
Her Britannick Majesty's Consul at New York.