IMPROVEMENTS IN THE MANUFACTURE OF ORDNANCE
Year: 1885

page_text: I PERCEVAL MOSES PARSONS of Melbourne House Blackheath in the County
of Kent Civil Engineer do hereby declare the nature of said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF ORDNANCE" to be as follows:-
For the purpose of my Invention I employ an alloy composed of Copper and
zinc in any of the proportions used for brass Muntz or yellow metal but by
preference one within the range of the latter to which may be added a small
quantity of tin from about one to three per cent also Iron or Iron and. Manganese
may be added which latter may be added in the form of Ferro-manganese in about
the proportions and in the manner described in the Specification of a Patent
No 482 granted to me and dated 7th February 1876 or by adding the Iron
separately by first combining it with the zinc and the Manganese by reducing its
black or other Oxide and combining it with the melted Copper in the presence of
Carbonaceous materials in the manner described in the Specification of a Patent
No 12288 granted. to John Davie Morries Stirling and dated 12th October 1848 but
the addition may be effected in, any other suitable manner-If the Manganese be
increased beyond one per cent then for every additional one per cent of Manganese
the zinc may be reduced from about 2 to 2 per cent.
"
To form the Gun or the Gun tube or shaft or the hoops or jackets or the like
I cast the alloy in chill or metal moulds which are made in two or more parts
separable longitudinally the surfaces which come together being planed or faced so
as to make a good joint and the parts being held together by hoops or clamps
which may be driven or forced on if the exterior of the mould be of a conical or
taper form or by hoops clamps or bands with wedges driven in between them and
the mould or. by screw bolts or other suitable fastenings. The interior. of the
mould is made to suit the form. of the gun or inner tube or shaft thereof intended
to be cast but is made somewhat longer. at the top end and the mould is there
enlarged in diameter so as to form a basin to contain a supply of liquid metal to
feed the casting as it cools and contracts For Guns up to a certain size say of
about 8 inches to 9 inches calibre the gun may be cast in one piece but for larger
sizes I cast onto the inner tube or shaft of the Gun one or more jackets or hoops
as may be required in the following manner. The inner tube or shaft of the Gun
having been already cast as before described I envelop so much of its length at the
breech end as requisite with a metal mould in two or more parts separable longi-
tudinally and held together by rings clamps or screw bolts as hereinbefore described
and I continue this mould a sufficient distance above the end of the Gun tube or
shaft I then pour the molten alloy into the annular space between the Gun tube
or shaft and the mould.allowing it to rise sufficiently above the end of the gun
tube or shaft.so as to form a head or, feeder to the jacket thus cast onto the inner
tube or shaft.

page_text: When the inner tube or shaft of the Gun is intended to receive a jacket as above
described I provide on it a shoulder or shoulders near the breach end and another
shoulder or other shoulders a short distance within the length of the jacket at the
other end as shewn at b b in Figure 2 so that when the jacket is cast onto the inner
tube or shaft it will not only shrink upon it and grasp it circumferentially but by
reason of the shoulders which it will envelop or overlap at each end it will by its
contraction hold and restrain the inner tube or shaft longitudinally. If required
another jacket or more than one can in like manner be cast onto the first one."
In Figure 2 the block at a' is formed or fixed on the breech end of the inner
tube or shaft for the purpose of guiding the head of metal into the space between
the said shaft and the mould.
When the casting of the Gun is complete I bore it out to a diameter slightly less
than the intended calibre and rifle it to any form required I then force through the
bore a series of dies or taper mandrils made of hardened steel or other sufficiently
hard metal-the series being of gradually increasing diameter and having projections
or grooves thereon corresponding to the form of the rifling so as to expand and
harden the rifled surface of the bore and put an initial tension onto the exterior of
the inner tube or shaft of the Gun after it has been rifled.
When the Gun is intended for a breechloader I construct the breach loading
arrangement as follows This I will describe with reference to Figures 3 to 6.
Figure 3 being a longitudinal section. Figure 4 an end view. Figure 5 a part
of Figure 3 drawn to a larger scale and Figure 6 a modification as hereinafter
described I first bore out the breech end for a short distance (from to y)
to a diameter slightly larger than the bore or powder chamber C, and in this
enlarged part I cut a female screw thread with a coarse pitch which may be a
double or treble thread if necessary and I provide a breech block D of a cylindrical
or slightly conical form with a corresponding male thread cut upon it. The breech
block D has a central axis d projecting from its outer end which passes through a
socket e at the end of a moveable arm E and is supported by it. The arin E is
mounted to move longitudinally and turn in strap pieces e its end being angled to
constitute a pivot for this purpose. Outside this arm E is a boss d² fixed on the
axis d of the breech block and beyond this is mounted so as to turn freely on the
axis d but confined longitudinally a double (or single) lever F The lever F and
the boss d² are shewn as being provided with tappets ff by which the breech block
is screwed into and out of its place but of course the tappets may be dispensed
with and the lever F be attached firmly to the spindle d. When the breech block
is screwed out of the breech of the gun (as shewn by the dotted lines in Figures 3),
the arm E is carried with it sliding in the straps e³ the breech block is then swung
on one side (as shewn by the dotted lines in Figure 4) and the charge being
introduced the said block is swung back again and screwed up. A roller G having
grooves or a thread or threads on its periphery corresponding to the thread or
threads of the screw cut on the breech block, and in the path of the female thread
in the breech of the gun, turning freely on a pivot g, is fixed on the breech end of
the gun, so that when the breech block is swung into position for being screwed up
it will rest upon or against the said roller in the correct position for entering the
breech and the threads naturally engaging the grooves in the roller the roller will
act as a support and guide and enable the breech block to enter and be screwed up
easily and expeditiously. For small guns a small fixed projection without a roller
but having the female thread continued on it will be sufficient.
For the purpose of making the joint gas tight I employ a cup or cupped ring H.
of metal attached to the face of the breech block as described in the Specification
of a Patent No 2876 granted to me and dated 17th November 1863 with this
improvement according to my present Invention videlicet that I make an annular
recess (at c) in the entrance of the bore to receive the cup or cupped ring and
1 undercut the inner end of the recess with an inclined or bevilled surface as at c³
so that it may slightly overlap the edge of the cup or cupped ring c³ when it
is inserted into its place and so press its edge against its seat in the bore and thus