IMPROVEMENTS IN GUNS, GUN CARRIAGES, AND PROJECTILES
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the Office of
the Commissioners of Patents on the 17th January 1882. A communication
from abroad by David Mefford Mefford of Toledo, Ohio, United States of
America, Mechanical Engineer.
WILLIAM ROBERT LAKE of the Firm of Haseltine Lake and Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN GUNS, GUN CARRIAGES,
AND PROJECTILES." [A communication from abroad by David Mefford Mefford of
Toledo, Ohio, United States of America, Mechanical Engineer.]
This Invention relates partly to carriages for siege and naval guns in which the
gun is arranged to slide upon an adjustable tilting frame, and in which, as the gun
recoils, it is met by an elastic resistance which serves to take up the shock.
The objects of this part of my Invention are to simplify and improve the means
for admitting of the sliding movement of the gun upon a tilting frame, and also to
provide an improved construction and arrangement of the slidable gun, the tilting
frame for supporting it, and the elastic resistance for taking up the shock incident
to the recoil, and for throwing the gun forward after the recoil.
I provide a strong metal frame composing the lower part of the carriage or
foundation for supporting the weight of the gun and the adjustable tilting frame in
which the gun is mounted. This foundation will be braced by means of suitable
tie rods and it is adapted to be rigidly secured to the ground or deck, or other
suitable foundation, by means of appropriate fastening devices which can be
arranged so that the carriage can be swung around when desired. The upper
horizontal portion of this carriage is formed with bearings for the trunnions of the
adjustable tilting frame, the said trunnions being fitted to articulate and turn about
their axes in these bearings, and being held down by suitable cap plates.
The tilting frame comprises two parallel metal side bars between which the gun
is arranged to slide, these side bars being provided with trunnions as aforesaid and
rigidly connected together by curved cross-bars which pass under the gun.
.
To admit of the longitudinally sliding movement of the gun within this tilting
frame and in a line coincident with the axis of its bore, and also to support the
gun upon the carriage, I cast the gun with longitudinal flanges or ledges on opposite
sides, and in the inner walls of the side bars of the tilting frame, I form horizontal
TD 31

page_text: recesses which receive the side flanges of the gun. These channels are each of
greater length than the flange which they receive so as to admit of the gun being
thrown backward by the recoil or moved forward after the explosion by means of
the resistance against which the recoil has backed the gun.
The resistance to the recoil of the gun is in the nature of an elastic cushion
formed by means of compressed air within two cylinders that are secured to the
side bars of the carriage and provided with a piston, the rods of which extend
forward and are connected in any suitable manner with the side flanges of the gun.
At the moment of recoil the pistons thus held in rigid connection with the gun will
be driven backward within their respective cylinders and hence forcibly compress
the air therein. The compressed air within the cylinders constitute elastic cushions
which receive and take up the shock of the recoil, and which, after the explosion,
drive the pistons toward the front ends of their respective cylinders and hence
move the gun forward until the side flanges of the latter abut against elastic buffers
arranged at the front ends of the grooves in the frame.
The openings in the cylinder-heads through which the pistons pass have each a
greater area than the diameter of the piston-rod, or the cylinders can be entirely
open at such ends so that when the air within the cylinder is compressed at one
side of the piston, there will be no tendency to create a vacuum in the cylinder at
the opposite side of the piston. I provide inwardly opening valves with which the
pistons are provided so that as the pistons move forward the valves will open and
allow the inflow of air into the cylinders, thereby compensating for any leakage
which may have occurred.
It will be obvious that practically the same effect could be obtained by creating
a partial vacuum within the cylinders instead of compressing the air as just
described. In such case the piston rod could work through a stuffing box at the
front end of the cylinder and an outwardly opening valve be provided at the rear
end of the latter, and, if preferred, the cylinders could be arranged in front of the
flanges of the gun instead of at the rear of the same and suitable valves be provided
so that the pistons will operate to create a vacuum within the cylinder when they
are driven back by the recoil. An elevated screw is connected with the rear end of
the tilting frame so as to tilt and adjust the latter for the purpose of righting the
gun. Such connection can be made by passing the screw through the curved cross
bar at the rear end of the tilting frame and upon the upper end of the screw fitting
a head or nut. By this means the frame can be tilted with a positive movement
and all vibration incident to the firing of the gun, completely avoided.
It will be seen that but one piston and cylinder could be employed, although I
prefer to use two.
Although various kinds of guns can be provided with side flanges, and used in
connection with the tilting frame hereinbefore described yet I prefer to use the
gun which constitutes another part of my Invention and which is constructed as
follows;-
I make the gun with two concentric cylinders, preferably of cast iron. These
cylinders are of any approved form and are reinforced in any suitable manner.
Neither of these cylinders should be any thicker than will ensure a perfect
crystallization of the metal. When large guns, formed of metal of such thickness as
to give sufficient strength to enable them to withstand the great strain they are
subjected to in firing, are made of a single casting, even when cast upon the most
approved methods, the metal is too thick for the formation of a perfect union
among its particles, and although the metal next the cooling core, or that next the
flask, may crystallize properly to a certain extent, yet in cooling and forming an
inside and outside shell, intermediate between the two shells, is formed a boiling
mass of metal which occupies a greater space in its highly heated state than it does
when cold. This intermediate mass cannot properly fill the prescribed space except
by granulating, and hence all of such intermediate section has but little, if any,
strength to reinforce the surface of the calibre. I am aware that cast iron has not
the textile strength of steel, wrought iron, or bronze, but the last named metal is

page_text: too costly for making very heavy guns, while the two first named are liable to
unavoidable flaws in welding. I therefore prefer cast iron on account of its
cheapness and freedom from flaws, although the inner or calibre cylinder may be
made of wrought iron, steel, or bronze.
I introduce water or other non-compressible fluid into the space between the
outer cylinder or shell and the inner or calibre cylinder as a bond of union between
the two, so that when the annular water chamber is full and the stop-cocks closed,
the calibre cylinder is fully reinforced by the outside shell and both the cylinders
being composed entirely of perfectly crystallized cast iron, great strength is ensured.
While this method of constructing a heavy gun does, not prevent the face of the
calibre from becoming heated in firing, yet it obviates the injury that the consequent
expansion of the calibre surface works in a gun that is made of one entire piece of
metal, for when my improved gun is being rapidly fired and the calibre surface
becomes expanded so as to cause the inside cylinder to expand and press against
the fluid in the chamber by simply opening the forward stop cock all strain on the
outer cylinder is at once relieved, for the excess of water over what is necessary to
fill the annular chamber will flow out, after which the stop cock must be again
closed before firing.
The fluid contained in the chamber also prevents a transmission of vibratory
motion from the inner to the outer cylinder, besides obviating any liability to
disintegration caused by successive strains resulting from unequal expansion of the
metal.
In filling the annular water chamber I attach a hose to the rear stop cock and
thereby connect the chamber with a suitable vessel containing the fluid to be
carried into the chamber. This is done by opening the stop-cock and raising the
vessel containing the fluid to a height above the highest point of the water
chamber. While this is being done the forward stop-cock must be open, and the
front end of the gun is preferably raised to a point higher than its breech. The
water will then flow in and completely fill the chamber, which is evidenced by its
flowing out at the forward stop-cock. On first filling this water chamber the gun
should be jarred to loosen any air bubbles and cause all the air to escape at the
forward stop-cock. Any fluid having the mechanical properties of water may be
employed and such liquids as freeze at very low temperatures only and are not
corrosive may be employed to advantage, and in some respects may be preferable
to water, such for instance, as solutions of alkaline salts, alcohol, or liquid
caoutchouc.
My Invention also relates to that class of shot which are adapted to be projected
from ordnance, and which are known as elongated projectiles.
In carrying this part of my Invention into practice I construct the projectile so
that it will approximate nearer in form to a dart or arrow than the elongated
projectiles heretofore made for ordnance, such conformation being due both to the
taper and to the great length thereof. In order to attain such an excess of length
over the ordinary solid elongated projectile and at the same time to prevent an
excess of weight I form the main body of the projectile of wood or other suitable
light material, which is armed with a pointed metallic head. The diameter of this
metallic head will be about one half the diameter of the butt or rear end of the
projectile and it can be made either of a single piece of cast or wrought iron or
steel, or it can have the point formed of steel, and a section of wrought or cast iron
be arranged between such steel point and the wooden body both for weight and
for the purpose of reinforcing said steel point.
The wooden body of the projectile has a reinforcing metal cap or plate secured
to its rear end to prevent the wood from being broken and shattered by the shock
of the discharge incident to the explosion of the powder within the cannon. This
rear metallic cap is connected with the metallic head of the projectile by a stiff
shaft of wrought iron or steel which passes through the axis of the wooden body
and is suitably connected with the said two metal ends of the projectile. This not
only saves the wooden body of the projectile from being crushed and knocked out

page_text: of shape by the shock of discharge, but it also serves to give great momentum to
the projectile by reason of its length and weight hereby giving great penetrative
power to the projectile.
When the projectile is to be used in rifled cannon, I arrange lugs of soft metal
such for example, as brass or copper, at its rear end, and also at some point on its
body nearer the head, on the head itself which lugs will fit into the groove of the
bore so as to support the head of the projectile centrally in the bore when it is
loaded into the gun. In using my projectile for smooth bore guns I dispense with
the soft metal lugs at the rear end of the projectile, and in lieu thereof provide a
metal band preferably of soft metal. This band will be of such diameter as will
admit of the projectile fitting the bore of the gun as closely as possible, due
allowance being made in such case for its contraction or expansion, by reason of
atmospheric changes, so that in either extreme of temperature the diameter of the
rear end of the projectile will approximate as closely as possible to the diameter of
the bore of the gun. By reason of this metal band a slight space known as the
windage" will be left between the rear cylindrical portion of the wooden body.
of the projectile, and the wall of the bore so as to allow for the expansion of the
wood by moisture absorbed from the atmosphere. The projectile for a smooth bore
gun will also have a suitable number of laterally projecting wings for centering
the head and maintaining the axis of the projectile coincident with the bore of
the gun.
"
The long wooden body of the projectile, for a portion of its length at its rear or
butt end, is made cylindrical so as to fit the bore of the gun and thereby aid in
maintaining the point of the projectile in the axial line of the calibre. The wooden
body of the projectile tapers from this cylindrical rear portion to its forward end
to which latter is applied the metal head.
This head may be composed of a steel point which consists of a cylindrical, or, if
preferred, a slightly tapering body having a sharpened forward end. The rear end of
this steel cap or point is concaved so as to receive and fit closely the conical end of
a metal reinforcing section and weighted piece which is of wrought or cast iron or
other suitable metal. This section fits upon the end of the wooden body and
is concaved to receive the conical end of the latter. To further secure a firin joint
between the two, the wooden body is made with an annular shoulder at its
forward end, and the metal reinforced section or weighted piece is adapted to fit
snugly upon the same; the flanged metal reinforcing cap is fitted to the rear end
of the wooden body.
A metal shaft passes through the axis of the wooden body. It also passes
through the reinforcing section of the head and has its forward screw threaded end
secured in a screw socket formed centrally in the steel point of the head. The
shaft at its rear end is also screw-threaded and passes through the metal cap at the
rear of the projectile, a suitable flat nut being secured upon said shaft and
tightened up against the cap. That portion of the shaft which passes through a
metal reinforcing plate is, by preference, not screw-threaded, and the screw-thread
upon the end of the shaft for receiving the nut is made very light so as to allow the
momentive force of the shaft to strip the slight screw-thread and permit the shaft
to accompany the head in penetrating the object fired at, leaving the wooden body
behind at the point of contact.
The reinforcing cap or plate at the rear end of the projectile will be provided
with soft metal lugs when it is to be used in a rifled gun. Laterally projecting
wings at its forward end are necessarily considerably wider than the lugs at the
rear end of the projectile. The reinforcing section will, in this instance, have a
dovetailed groove in opposite sides to receive tongues upon said ways, these grooves
being wedge-shaped or tapering from front to rear, and the tongues having a like
conformation so that at the discharge there will be no liability of the wings being
driven back upon the wooden body.
In place of the wings for the rifled bore I may employ wings suitable for smooth
bore.cannon. These wings consist of pieces of wood with the grain running

page_text: coincident with their length and they are fitted in mortices formed through the
wooden body of the projectile and abut against the central shaft. These wooden
pieces extend out laterally from the projectile and serve to steady and support the
point of the projectile centrally in the bore. If desired, a circular metal band can
be secured to the ends of the wings to further strengthen the same although such
will hardly be found necessary.
For a smooth bore gun, at least three wings should be employed; for a rifled gun
two can be used with good effect.
These wings could be connected with the head of the projectile in other ways, or
provision can be made for connecting them with the wooden body back of the head,
as for example, by metal strips or plates extending back from the head and sunk
into the wood, or by means of a metal band. This latter method, that is to say, the
employment of a metal band fitted upon the tapering wooden body is, however, the
one which I prefer. This metal band may be from three to eight inches long,
the inside surface made tapering to conform with the taper of the wooden stock.
The front of the band should be thin so as to offer no obstruction to the air and
the raised beads on said head be either coincident with the axis of the projectile or
they may be slightly spiral so as to cause a rotation in the flight of the projectile.
The extreme diameter of these beads or flanges should fit the calibre nicely. This
device is only for smooth bore guns, and when it is employed the rings attached
to the head are dispensed with.
I would remark that to be fully effective the length of the projectile should be
of at least equal to five diameters of the bore of the gun in which they are intended
to be used.
In forming the projectile for smooth bore cannon, if it should be desired that the
projectile shall twist or revolve in its flight, the forward ends or edges of the wings
can be bevelled so that the resistance of the air will cause the projectile to rotate
about its axis.