IMPROVE-. MENTS IN BREECH-LOADING ORDNANCE
Year: 1867

page_text: PROVISIONAL SPECIFICATION left by Alexander Melville Clark at the
Office of the Commissioners of Patents, with his Petition, on the 2nd July.
1867. A communication from abroad by William Armstrong, of 29,,
Boulevart St. Martin, Paris.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, do hereby declare the nature of the said Invention for "IMPROVE-.
MENTS IN BREECH-LOADING ORDNANCE," to be as follows:-
This Invention which relates to improvements in breech-loading ordnance;
is illustrated in the accompanying Drawings, Figure 1 showing a longitu-
dinal section of the breech end of a gun on the line 1, 2, Figure 2, which is
an end view of the same; Figure 3 is a horizontal section of the gun on the
line 3, 4, 5, 6, Figure 1; Figure 4, an end view of the breech on the line 7, 8,
Figure 3; Figure 5, a separate longitudinal section of what I term the charge.
carrier; Figure 6, a transverse section of same on line 9, 10, 11, 12, Figure 5;.
Figure 7 shows a detached view of what I term an excentric axis, taken on
line 18, 14, Figure 8, which is an end view of same; Figure 9 shows sepa-
rately in end view a part serving to fix the charge carrier in the breech;.
Figure 10, a transverse section on line 15, 16, Figure 9, and Figure 11, a plan
of same; Figure 12 shows a longitudinal section on line 17, 18;. Figure 13.
of a mode of constructing the charge carrier, and Figure 14 an end view
of same on line 19, 20, Figure 12. The same letters serve for all these
Figures.
The general form of the gun is the same as usual, and this Invention may
consequently be adapted to existing guns.
The Invention consists in the peculiar construction of the interior of the
gun, more especially in the arrangement. of the first reinforce and breech,

page_text: which I combine in such manner as to receive one of the cartridge holders B,
Figures 5 and 6, à supply of which is provided for the gun, it being placed
in a space 0, 0, made in the breech for its reception; this space, which may
be made either.above, below, at the side, or even through the breech, is
formed so as to accurately receive the cartridge chamber, its internal diameter
corresponding to that of the bore of the gun. The breech end of the gun
is
also bored through of the same diameter as the barrel to receive an eccentric
axis C, Figure 8, which together with the wedge D, Figures 9, 10, and 11,
serves to press the cartridge chamber up against the second reinforce. This
axis C on being rotated about one-fourth of a turn by the aid of a hand lever F
raises the wedge D and draws back the striker E about half its extent of
traverse, when by a reverse movement of the hand lever the wedge D is
returned to position, which in bearing against the cartridge chamber obliges
the striker to perform the other half of its traverse, rendering it free to act on ;
the percussion cap G by the aid of a spring H fitted in the end of the eccentric
axis C which closes the breech end of the gun.
Action. In order to manoeuvre the gun three simple and expeditious
motions only are required. 1st, the hand lever F is brought to the position
A, A, Figure 2, which raises the wedge D and forces back the striker E to
the extent of half its traverse; 2ndly, a chamber B containing the charge is
then placed in the cavity O, O, by the aid of the handles X; 3rdly, the hand
lever F is then moved back to the point B, B, Figure 2, so as to bring the
wedge D up' against the cartridge chamber and so fix the latter in position in
the breech. During this movement the striker performs the second half of
its traverse, and at the moment the hand lever F is brought to the point B, B,
the striker is free to escape and strike the cap for the purpose of discharging
the gun.
Advantages. 1st, there will be no danger of overheating, as the cartridge
chamber which is the only part liable to become heated. to a sufficient extent.
to prevent the gun from being worked is replaced by a fresh one after each
discharge; 2ndly, there will be no appreciable fouling, as the cartridge chamber.
can be easily cleaned after being removed from the gun; 3rdly, from the sim-
plicity of the action and the advantages above mentioned, it follows that the
gün may be fired much oftener in a given time than otherwise; 4thly, in
consequence of the position of the nipple J the flame may be introduced either
at the centre of the charge or as near the projectile as desirable; the powder
in this manner will be entirely consumed, thus obtaining considerable economy
as compared with other systems, which either drive out or burn a great
quantity of the powder after it has left the barrel; 5thly, there is a further

page_text: advantage in possessing a ready means of rendering the gun useless without
injury, if desired, which may be readily effected by withdrawing the pin K,
and removing the wedge D, together with the eccentric axis C, which form
the indispensable portions of the
gun.
•
Mode of Constructing the Charge Chamber.-In order to prevent the
accidents which often occur through the unequal expansion of the several
metallic layers of which the barrel of the gun is composed after successive
discharges, which expansion is much greater in the interior than on the
exterior through the difference of heat, and is the cause of invisible cracks
that continually increase until they terminate in the bursting of the piece.
To obviate this I propose to make the charge chambers of coils of steel on an
iron core or foundation, as seen in Figures 12 and 13, which I combine in
such manner that when the charge chamber is completely formed the iron
portion may be removed by boring and turning. In order to make the body
of the charge chamber in a ready manner consistent with strength I coil on
the iron core a sufficient amount of square steel wire a, which I then cover with
a tube of iron 6; I place the whole thus prepared in a puddling furnace, where
by hammering it is formed into a compact mass, which is then bored and
turned as before mentioned. In this manner I obtain a metal which will
safely resist a pressure equivalent to 7500 atmospheres, the external diameter
of the charge chamber being double that of the bore of the gun.
The destruction of the joints in breech-loading guns is occasioned by the
enormous pressure of the gases, which is however, reduced to a third or fourth
part of the original pressure before they arrive at the joint in the improved
construction of gun of this Invention, as the ball must travel a distance
equal to its whole length before the gases reach the joint between the charge
chamber and the barrel; two-thirds or three-fourths of the pressure being thus
expended on the projectile. And in order to prevent all escape of gas I propose
to place a ring of copper or other metal in the base of the projectile of the
same diameter as that of the interior of the charge chamber; this ring being
projected with the ball is arrested in its flight on reaching the rifling of the
barrel, which is of smaller diameter, and is there held firmly at the junction
of the parts by the pressure of the gases, which are thus prevented from
escaping at the joint.