Improvements in or relating to Projectiles for Ordnance.
Year: 1896

page_text: Date of Application, 3rd Jan., 1896
Complete Specification Left 3rd Nov. 1896-Accepted. 3rd Feb.. 1897
Improvements in or relating to Projectiles for Ordnance.
I, DAVID MEFFORD MEFFORD of Allison's Hotel, 13 Charterhouse Square,
in the City of London, Engineer, do hereby declare the nature of this invention to
be as follows:-
This invention relates to projectiles for heavy ordnance, the object of which is
to obtain all the advantages possessed by projectiles for that purpose now in use,
without their disadvantages. The present copper band of the projectile for heavy
ordnance performs but two functions, one of which is cutting off windage, the
other, rotating the projectile while passing through the curving rifled grooves of
the calibre, but in accomplishing these, unavoidable friction is produced, which is
detrimental both to the gun and to the range of the projectile.
To avoid the disastrous friction incident to the copper packing band and to
facilitate the movement of the projectile this invention is provided with preferably
three antifriction ball bearing wheels inserted in the projectile near its forward
end, placed equidistant in line encircling the projectile and obliquely seated as
nearly as may be in line coincident with the spiral grooves of the gun. These
wheels are not intended to run in the grooves but on the lands of the gun, and
designed to hold the front end of the projectile centrally in the calibre. At the
rear end preferably three studs are firmly inserted and adjusted to fit the three
rifles of the gun. The wheels sustaining the front end and rolling obliquely to
the axial line of the projectile become efficient aids to the studs in rotating the
projectile.
Although the employment of wheels is preferable, yet short studs or the
equivalent may be employed instead thereof at the front end of the projectile to
slide on the lands of the gun, for centralling purposes.
For the purpose of utilizing the full force of the charge, in driving the projectile,
circumferential grooves are provided near the rear end of the projectile, the rear
sides of which grooves slope forward, the forward sides are under cut and curved
backward, the function of which is to create gas packing by producing cyclonic
action in the gas forced between the face of the calibre and the projectile, and
any gas forced over the first groove, is caught in the second, and any escape from
the second is caught in the third, and so on, so that they absolutely prevent any
escape of gas before the projectile leaves the muzzle of the gun. They not only
accomplish this, but they present a pushing surface, by the backward curving
walls of the grooves against which the arrested gas is forced to aid in driving the
projectile forward.
Another advantage results from this plan for gas checks.
The metal removed in forming them, moves the centre of gravity forward of
the centre of figure, thereby making the forward end heavier than the rear end,
which prevents the projectile from reversing or tumbling end over end in its flight.
Dated this 3rd day of January 1896.
BOULT & WADE,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Projectiles for Ordnance.
I, DAVID MEFFORD MEFFORD of Allison's Hotel, 13 Charterhouse Square,
in the City of London, Engineer, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
This invention relates to projectiles for heavy ordnance, the object of which is
to obtain all the advantages possessed by projectiles for that purpose now in use,
without their disadvantages. The present copper band of the projectile for heavy
ordnance performs but two functions, one of which is cutting off windage, the
other, rotating the projectile while passing through the curving rifled grooves of
the calibre, but in accomplishing these, unavoidable friction is produced, which is
detrimental both to the gun and to the range of the projectile.
These drawbacks are avoided in constructions according to the present invention
illustrated by way of example in the accompanying drawings wherein
Fig. 1 is a side elevation of one construction of improved projectile according to
this invention.
Fig. 2 is an elevation, with part removed, of a detail of Fig. 1, and
Fig. 3 is a section on the line 3-3 of Fig. 2,
Figs. 2 and 3 are drawn to a larger scale than that of Fig. 1.
Like letters indicate like parts throughout the drawings.
In Fig. 1 the projectile has towards its forward end a zone or band preferably of
three wheels or rollers A intended to run upon the lands of the gun and a similar
zone preferably of three studs or projections B at the back end, these studs being
intended to run in the rifle grooves of the gun, and impart the rotation, while the
wheels or rollers A support the weight of the forward end of the projectile. The
wheels are carried in casings C and are preferably set obliquely as indicated in
the drawing so as to properly follow a helical path as the projectile travels through
the gun.
Fig. 2 is a side view with part removed, and Fig. 3 a cross section of the wheel
casing showing how the wheel is carried. The wheel or roller A is supported upon
an axle A fixed in the casing C which is let into an appropriate opening in the
wall of the projectile and fixed therein in any convenient manner say by screwing
it bodily in, or by two or more screws threaded partly into the casing C and partly
into the projectile, engaging with both. The wheel A is recessed on both sides
so as to provide ball races for two rings of balls A' which otherwise bear upon the
fixed axle A' and the casing C. By this arrangement the wheel is free to rotate
at any required speed, and as that is only intended to be accomplished in the one
journey through the gun it is not necessary to provide means for taking up wear
in the bearing. A loose cap or picce C' allows the necessary access for inserting
the various parts, a screw C serving to fix this loose piece.
Although the employment of wheels is preferable, yet short studs or the equivalent
may be employed instead thereof at the front end of the projectile to slide on the
lands of the gun, for centralling purposes.
The gas-check grooves F forined in the surface of the projectile are undercut or
hollowed thus producing a cyclonic action in the grooves and forming an efficient
gas check. Any desired number of grooves may be employed and besides acting
as a gas-check they provide a pushing surface against which the arrested gas is
forced and would thus aid in driving the projectile forward, while the metal
removed in forming them lightens the back of the projectile, thus moving forward
the centre of gravity and making the forward end heavier than the rear end with
the well-known advantages consequent thereon.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is ;-
1. In a projectile the combination with a ring or zone of wheels or rollers or
studs at the forward end of the projectile of another ring or zone of studs at the
back of the projectile which latter are to engage with the rifle grooves of the gun
for the purpose of rotating the projectile.
2. In a projectile the combination of wheels or rollers to run upon the lands of
the gun with studs to run in the grooves.
3. The combination with a projectile of a wheel or roller and a ball bearing
for carrying it.
4. In a projectile a wheel or roller comprising a disc recessed on both sides a
fixed axle and two rings of balls.
5. The improved gas-check substantially as described.
Dated this 12th dow of October 1906
BOULT & WADE,
Agents for the Applicant.