IM- PROVEMENTS IN BREECH-LOADING NEEDLE GUNS, AND IN CARTRIDGES TO BE USED THEREWITH
Year: 1867

page_text: PROVISIONAL SPECIFICATION left by Friedrich Hahn at the Office of
the Commissoners of Patents, with his Petition, on the 30th March
1867.
I, FRIEDRICH HAHN, of Tavistock Street, Bedford Square, in the County
of Middlesex, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN BREECH-LOADING NEEDLE GUNS, AND IN CARTRIDGES TO BE USED
THEREWITH," to be as follows:-
This Invention relates to certain improvements in the construction of
breech-loading needle guns whereby rapidity of firing is effected and a
saving in the number of movements afforded, and also in the manufacture of
the cartridges to be used in such improved guns or in any other needle guns.
I propose to form the breech with an open space and to fill it in with a breech
plug which moves upwards and downwards with a parallel motion, which is
effected as follows:-The breech plug is joined beneath to a connecting rod
which is attached to a plate beneath the stock of the arm; this plate is hinged
or pivoted behind the trigger guard so as to allow it to fall and be raised in
order to bring down or restore the breech plug to its position to close or open
the breech. The plate is retained or released by means of a finger catch,
kept in position by a sear spring, and when pressed by the finger against the
action of the sear spring the plate is suddenly forced downwards and by a
mainspring, and thus brings down the breech plug; the cartridge is then
inserted on the top of the plug and pushed into the barrel; the plug is then
restored by forcing up the plate and fastening it by the catch; then a vertical

page_text: stem or hand lever connected to a cylinder in the hollow of the breech plug is
drawn back; this cylinder is actuated by a duplicate helical spring, one on.
each side, and the needle and shaft pass through the spring and are held by
the cylinder. The rear extremity of the needle shaft is provided with a jointed
detent or catch, which is thereby brought to the rear of the body of the gun,
and is furnished with a sear spring which forces the detent over a ledge or
notch and keeps the needle back. The trigger is placed just under this position,
so that when pulled it raises the detent over the notch and releases the needle
shaft, which is then propelled rapidly forwards into the cartridge; for it is evident
that although the two springs are equal when in a neutral position, yet that when
the rear spring is compressed the fore spring is relaxed or weakened, and there-
fore the rear spring has the greater power and forces the needle against the
action of the fore spring, but after penetrating the cartridge the needle shaft
immediately returns to its position free of the cartridge by the action of the fore
spring, which then exerts it powers. This constitutes the chief advantage over
the Prussian needle gun, where the needle remains in the barrel. The
slightest amount of penetration of the needle will suffice to ignite the ignition
substance; it is therefore not necessary for the needle to penetrate.com-
pletely through, as is the case in the Prussian cartridge, thus preventing all
chance of the breaking of the needle. It is evident that by this improved con-
struction of breech-loader only five movements will be required, viz., the open-
ing of the breech by the left hand, the insertion of the cartridge, the closing of
the breech plug, the action of the needle shaft, and the discharge by the right
hand; and all these motions are effected without changing the position of the
The two movements of opening and closing are done by the left hand,
and thus the five movements are virtually reduced to three.
arm.
The cartridge consists of a casing of vegetable parchment or paper, treated
with sulphuric acid, although other material may be used. The case covers
or encloses the projectile, the powder, and the detonator, and is discharged
with them, thus leaving no deposit or corrosion in the gun. The peculiarity
in the cartridge consists chiefly of the detonating or ignition substance or fuse,
and in the arrangement or placing of the same. The ignition substance is
composed of the following ingredients, viz.,-
Chlorate of potash
Picric acid
Amorphous phosphorous
20 parts by weight.
5 do.
do.
5
do.
do.

page_text: into a paste; I then form a small hollow cylinder, ring, or tube of wood or
other material about half the diameter of the cartridge, and I attach thereto
three or four arms or supports equal to the interior diameter of the cartridge;
this I term a "mirror;" I then fill the internal ring or space with the com-
position, and it sets and hardens therein; I then place the ring with its
supports in the cartridge case, and fill the space between it and the bullet with
gunpowder, which also surrounds and comes behind the ignition substance, so
that the ignition substance is embedded and surrounded on all sides with
the powder, and thus a central and gradual fire is effected, consuming all
the powder employed. The penetration of the needle ignites by friction the
ignition substance, and thus discharges the contents, carrying out the vegetable
parchment case, and cleaning the gun. The portion of the cartridge where
the needle penetrates may be made thinner than the main body, but it is not
absolutely necessary.