IMPROVEMENTS IN BREECH AND MUZZLE-LOADING CANNON, GUNS, AND OTHER FIRE-ARMS, AND IN PROJECTILES TO BE USED THEREWITH
Year: 1864

page_text: PROVISIONAL SPECIFICATION left by Richard St. Leger Pigot at the
Office of the Commissioners of Patents, with his Petition, on the
16th February 1864.
I, RICHARD ST. LEGER PIGOT, of Charles Street, Berkeley Square, in the
County of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN BREECH AND MUZZLE-LOADING CANNON, GUNS,
AND OTHER FIRE-ARMS, AND IN PROJECTILES TO BE USED THEREWITH," to be as
follows:-
My Invention relates, firstly, to cannon, guns, and other fire-arms, both
smooth bore and rifled, in which the charge is introduced at the breach.
Secondly, to the mode of rifling cannon, guns, and other fire-arms.
Thirdly, to projectiles for use in the same, and to projectiles for use in
muzzle-loading cannon, guns, and other fire-arms.
Fourthly, to the conversion of old smooth-bore cannon, guns, and other
fire-arms, into breach-loaders.
Fifthly, to an internally-rifled cylindrical shot for use in smooth-bore or
rifled cannon, guns, and other fire-arms.
To apply my principle of breech-loading, the cannon or gun is to be bored
clean through, and part of the bore at the breech end is made somewhat
larger than the other part of the bore to receive a solid screw plug with
handle; at the side of the cannon or gun, at the breech end, and a little in
the rear of the vent, is a hole or slot inclining inwards to the bore or screw
hole, large enough to receive the charge. The vent is pierced in the cannon
n the usual way.

page_text: My solid screw plug with handle is made of wrought iron or other metal,
and consists of a solid screw plug with handle to work it all in one piece.
My solid screw plug is made somewhat larger than the bore of the gun, and
is of easy-working threads to correspond with the screw grooves in the part of
the breech of the cannon or gun made to receive it. The top or end of my
solid screw-plug is wedge-shaped, and somewhat larger than the bore of the
cannon or gun, which at the breech end is made to receive it. The sides of
this top or end of the screw plug is to be covered with oiled felt to cause it to
fit tightly and prevent any escapement. The screw plug is prevented from
being withdrawn too far out by means of a stop which may consist of a chain
affed at the one end to a loose collar around the neck of the solid screw
plug, and at the other end by a hook, casily fastened and unfastened, to the
gun, or by any other description of stop applicable thereto. The advantages
of my solid screw plug are, that it may always be kept in the breech of the
gun, or may be withdrawn at any time, and so the gun rendered useless to the
enemy. The action of the screw plug is thus described:-When the gun is
to be loaded tho screw plug is turned by the handle and unscrewed to tho
stop; the charge is then placed into the slot or hole right before the screw
plug, which is then screwed up tight and propels the charge into the chambor
or bore; the screw plug is then tight and the gun fit for firing.
loading cannon can be used as a muzzle-loader if required.
My breech-
My mode of rifling cannon and other guns consists of several semicircular
grooves gradually becoming larger from the muzzle towards the breech end
and ending gradually in the breech.
The projectiles to be employed with my breach-loading cannon, either rifled
or smooth bore, may be of any known description or size. My improved shell
consists of an outer case of cast iron pierced with holes for rivets or plugs of
a length equal to the thickness of the shell. The shell being heated, the rivets
or plugs are inserted cold; when the shell cools the rivets or plugs will be
tightly held until the shell is exploded. The rivets or plugs may be inserted
in any other convenient way. The shell, except where the fuze is inserted, is
packed with diamond-shaped segments of cast iron, which, on the explosion of
the shell, will be dispersed on every side. The fuze will be inserted in the
usual way. This shell may also be used with muzzle-loading guns.
My internally-rifled cylindrical shot consists of a cylinder of iron or other
metal, the outer diameter equal to the bore of the gun in which it is to be
used, the inner diameter to depend on the weight of the shot required. The
head of the shot to be flat or convex or concave. The hollow centre is to be
of a circular, oval, or polygonal shape. The hollow centre is to be rifled with

page_text: rifle or screw threads or raised flanges of any size or twist. The rifling of the
shot may be either of a uniform guage throughout or larger at the front end
and decreasing in size at the rear, and the hollow centre inay be of uniform
size throughout, or larger at one end than the other. The internal rifling aud
shape of the hollow centre of this shot is to impart to it on leaving the gun
a rotary motion by means of the air rushing through the grooves in the sides
of the hollow centre. With a coating of oiled felt this rifled shot may be used
for rifled guns. This shot is applicable to breech and muzzle loaders. In
firing a washer of metal or other material is to be placed between the charge
and the shot to prevent the force of the explosion passing through the hollow
centre.
Figure 1 of the Drawings hereunto annexed represents a cannon constructed
according to my Invention, shewing the slot or hole, marked A, through which
the charge is placed in front of the screw plug; B is the handle of the screw
plug.
Figure 2 represents a section of my breech-loading rifled cannon; C shows
the rifling and bore; D shows the screw hole in which my solid screw plug
works; E shows the position for the elevating screw to be attached to the
cannon; shows the position of the vent in the cannon.
Figure 3 represents a section of an old gun altered to a breach-loading
cannon on my principle with the solid screw plug and handle in the breech.
Figure 4 shows the solid screw plug when out of the cannon's breech with
its loose collar and stop chain.
Figures 5 and 5ª show the bore and grooves of the rifling.
Figure 6 represents my shell and diamond-shaped segments and rivets.
Figure 7 represents one of the diamond-shaped segments in the shell.
Figure 8 represents one of the rivets in the outer case of the shell.
Figure 9 represents a front view of the shell with holes for the iron rivets.
Figure 10 represents a longitudinal section of one form of my internally-
rifled cylindrical shot.
Figure 11 represents a longitudinal section of another form of the said shot
with a differently-shaped hollow centre.
Figures 12, 13, and 14, represent cross sections of different varieties of
internally-rifled shots.