IMPROVEMENTS IN PROJECTILES FOR ORDNANCE
Year: 1876

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN PROJECTILES FOR ORDNANCE." A communication from
abroad by Norman Wiard, of Washington, District of Columbia, United States
of America.
Sealed the 30th June 1876, and dated the 8th May 1876
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 8th May 1876.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lako, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN PROJECTILES FOR ORDNANCE."
A communication.
This Invention relates to solid shot and shell used in connection with rifled
canuon, and it consists in the details of construction herein-after described.
In the present condition of national armanents a very large proportion of the
great guns on hand are of cast iron, smooth bored, and adapted only to spherical
shot. Such guns being almost obsolete, owing to recent improvements in armour
plating protection, it becomes a great necessity to improve means of offence by new
rifled guns, and an economical desideratum to utilize the smooth bored cast-iron
guns already on hand or mounted, and by some alteration to bring them, if possible,
up to the power required to overcome the defenccs of modern warfare.
The theory of artillerists from time immemorial has been that the weight of metal
in a shot as compared with the weight of metal in a gun should be about as one to
one hundred, or, in other words, about one pound avoirdupois in the shot to one
hundred pounds in the gun from which it is intended to be fired.
Rifled guns require such a length of shot compared with the calibre that the
bearing points of the projectile shall be sufficiently far apart longitudinally in
the bore to prevent the possibility of the longitudinal axes of bore and projectile
altering their coincidence while the projectile is in the bore, so that there may be
no risk of either abrading the gun or breaking off or abrading the guiding parts or
flanges of the projectile or the grooves of the gun. Cast-iron guns were formerly
cast for spherical shot, and the difficulty in now altering them to rifled guns is to
avoid a change of the necessary ratio between the weight of the shot and the weight
Price 8d1

page_text: of the gun, and at the same time obtain length of shot necessary for bearing points.
These objects I accomplish by producing a projectile which will combine in its body
a portion having the greatest capability for puncturing or penetrating, and a portion
calculated to receive and utilize the greatest amount of propulsion given from the
impulse of the explosion of a charge of powder possible to a given calibre and
weight of gun, and at the same time so lengthen the shot without increasing its
weight as to greatly extend the distance between its bearing points in the grooves
of the gun.
According to this Invention I make a projectile with a semi-subcalibre pune-
turing portion projecting from a base or sabot cast in one piece with it, the
sabot being of full calibre and provided with windage appliances and supporting
points.
The cylindrical base or sabot is adapted to the calibre of the gun to be used, less
the necessary windage, and is provided with grooves as windage appliances and
projecting soft metal (preferably copper) boutons to nearly centre the shot.
The puncturing portion is in solid projectiles of the heaviest calibre contracted
abruptly on two sides from the sabot towards the point, and in cross section in two
gradually receding curved lines, so as to make its shape lenticular in cross section,
its longest line being about equal to the diameter of the bore until the point of the
shot is neared, when all the lines are gradually contracted in true curves, forming
a blade or point resembling a Roman sword, the top of a bishop's mitre, or a mitten,
thus forming a shot which I call a "mitten" shot. In its longest axis the puncturing
portion is cast with a twist, so proportioned to the rifling of the gun that the
extremes of the lines of the lenticular cross sectional form are parallel to the lines
of the centro of the grooves of the gun.
Flanges for giving the shot a rotary motion are cast thereon to fit the grooves
of the gun, and are so located on the forward edges or lines as to properly hold the
shot and support it, and guide it along in the grooves. The bearing surfaces
of these flanges conform to the curvature and cross section of the grooves in the
gun. Two small flanges are cast near the sabot to enter, but not to touch, the
grooves, to check the windage through the grooves.
The projectile being cast with an abrupt contraction, and with a concavity in its
base, the proportion of the thickness of the metal is so arranged that almost simul-
taneously with the impact of the point of the shot against any resisting object the
momentum of the heavy sabot will expend itself in endeavouring to pass beyond the
puncturing portion, and the shock will break the sabot, if the resisting object
sufficiently impedes the shot's progress. The length of the puncturing portion should
be for projectiles to be used in altered smooth bore arms from its tip to the sabot
about equal to 14 times the diameter of the sabot, and in guns cast for rifling, the
puncturing portion should be from 1 times to twice the diameter of the sabot. But
it is necessary that all projectiles for altered guns should have the distance from the
centre of the boutons to the forward end of the flanges at least equal to the
diameter of the bore of the gun.
In experimenting it has been discovered that solid shots having gradually
declining curves combined with a deep recess in their butts fail and break in the
gun from the impulse of the discharge, their weakness resulting from unequal
tension caused by unequal cooling between the inner and the outer curved lines.
To overcome this difficulty, I cause these lines to recede more rapidly from each
other, and thereby obtain a shot so proportioned that it will cool with sufficient
uniformity to avoid the unequal tension. After the discharge of the gun, the
projectile rotates at a high velocity, and owing to its twisted formation penetrates
in the manner of a spiral drill or corkscrew. The shape of my projectile in its
cutting and puncturing point affords important results. Taking a side elevation
of the narrower side of the sub-calibre portion, the outlines conform to an ogaval
point upon a radius of about 1 diameter, while a side elevation of the broader
side of the sub-calibre portion shows a curvature of a greatly increased diameter,
the contracting or converging curves forming the cutting edges, so that I combine in

page_text: this improved point the puncturing capacity of tho ogaval point with the cutting
capacity due to the lenticular cross sectional form, while the greater width strengthens
and braces the ogaval shape in the narrow width.
The grooves around the sabot are perpendicular to the longitudinal axis of the
gun on the side next to the cartridge, and beviled on the side next to the point of the
shot, the pitch being about one to three. These grooves act in retarding the rapid
escape of gas by the instantaneous creation of a series of eddies within them,
and these eddies in turn prevent a rapid escape of gas directly through the windage
space..
Cored shots may have the bursting charge, which is introduced through the screw.
hole stopped by a plug in the slightly.convex butt, exploded by either a time or
percussion fuse or the charge, or by the heat of concussion. When advisable I
propose to introduce into the opening a paper cased meal-powder time fuse, or a
Boarman fuse.
.
Projectiles constructed as herein described, when made for guns cast for rifling,
allow a great increase of distance between the points of support in the grooves, the
shot is of a graceful appearance has a perfect tone in flight, a high initial velocity,
an extraordinary terminal velocity, a very low. trajectory, and great precision. I
have formerly chilled the projectiles down to a slightly descending curved lino
from the forward ends of the flanges, but now prefer to throw a chill in the form of
decreasing steps down between the flanges, for the reason that this chill aids
in cooling the thick part of the mitten-shaped portion, and thus prevents unequal
tension.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the 8th
November 1876.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN PROJECTILES FOR ORDNANCE"
A communication from abroad by Norman Wiard, of Washington, District of
Columbia, United States of America.
My Invention relates to solid shot and shells used in connection, with rifled
ordnance, and it consists in the details of construction herein-after described.
In the present condition of national armaments a very large proportion of the
great guns are of cast iron, smooth bored, and adapted only to spherical shot. Such
guns are almost obsolete, owing to recent improvements in armour plating pro-
tection, it has therefore become a great necessity to improve the means of offence
or attack; and an economical desideratum to utilize the sinooth bored cast-iron guns
already on hand or mounted, and by some alteration to convert them into rifled
guns, and give them, if possible, the power required to overcome the defences of
modern warfare. Alterations such as to bring these great guns to the capacity
required are involved in and fully described in my former Letters Patent, dated
14th March, A.D. 1874, No. 938.
'
The theory of artillerists from time immemorial has been that the weight of
metal in a shot as compared with the weight of metal in a gun should be about as
one to one hundred, or, in other words, about one pound avoirdupois in the shot
to one hundred pounds in the gun from which it is intended to be fired.
Rifled guns require a length of shot so proportioned to their calibre that the
bearing points of the projectile shall be sufficiently far apart longitudinally in the
hore to prevent the possibility of alteration of the coincidence of the longitudinal
axes of the bore and projectile, while the projectile is in the bore, so that there
may be no risk of abrading the gun or breaking off or abrading the guiding parts
or flanges of the projectile or the grooves of the gun. Cast-iron guns were formerly
designed for spherical shot, and the difficulty in now converting them into rifled

page_text: guns consists in avoiding a change of the necessary ratio between the weight of the
shot and the weight of the gun while obtaining length of shot necessary for
bearing points.
These objects I accomplish by producing a projectile which will combine in its
body a portion having great puncturing or penetrating capability, and a portion
calculated to receive and utilize the greatest amout of propulsive force produced by
the explosion of a charge of powder in a gun of a given calibre and weight, whilst
the manner of mounting it in the bore, according to the theory of my aforesaid
Specification, will be most favorable for preventing any waste of its power from
upsetting, indentation, undue friction, or permanent change of form of the gun or
projectile, or other retarding expenditure of force, while the projectile is passing
out of the gun, and at the same time so lengthening the shot or projectile without
increasing its weight as to greatly extend the distance between its bearing points in
the grooves of the gun.
According to my Invention, I make a projectile with a simi-subcalibre pune-
turing portion of a form herein-after described, projecting from a base or sabot cast
in one piece with it, the said sabot being of the full calibre and provided with
windage appliances, and supporting points as heroin-after more fully set forth.
In the accompanying Drawings, Figures 1, 2, and 3 are side views and a
transverse section of a solid shot or projectile constructed according to my
Invention.
Figures 7, 8, 9, Figures 13, 14, 15, and Figures 19, 20, and 21, are similar views of
my solid shots or projectiles.
Figures, 5, 6, Figures 10, 11, 12, Figures 16, 17, 18, and Figures 22, 23, 24, arc
similar views of my improved hollow shots or projectiles.
Figures 25, 26, 27, and 28, are side and end views and a transverse section of
another shot or projectile herein-after described.
B is a cylindrical base or sabot whose calibre is equal to that of the gun to be
used, less the necessary windage, and which is provided with grooves b, b, as
windage appliances, and projecting copper or other soft metal boutons c, c, to nearly
centre the shot, as described in the Specification of my said former Letters Patent,
and if the projectile is solid it has a conical recess E of a form herein-after described
and as shown in Figures 1 and 2.
The puncturing portion A is in solid projectiles of the heaviest calibre contracted,
as shewn in Figures 1, 2, and 3 (a 15-inch shot), abruptly on two sides from the
sabot towards the point, and in cross section in two gradually receding curved
lines a, a, to make its shape lenticular in cross section, its longest line being about
equal to the diameter of the bore until the point of the shot is neared, when all the
lines are gradually contracted in true curves forming a blade or point resembling a
Roman sword, the top of a bishop's mitre, or a mitten, as shown at d, d; I call the
projectile so formed a "mitten shot." In its longest axis the portion A is cast with
a twist so proportioned to the rifling of the gun that the extremes of the lines f, f.
of the lenticular cross sectional form are parallel to the lines of the centre of the
grooves of the gun.
Flanges for giving the shot a rotary motion are cast at D, D, to fit the grooves
of the gun, and are located on the forward edges or lines ff, to properly hold the
shot, and support and guide it in the grooves. The bearing surfaces of these flanges
are all in planes parallel with the lines, f, and conform to the curvature and cross
section of the grooves in the gun. Two small flanges D','D', are cast near the sabot
to enter but not touch the grooves to check the windage through the grooves. This
shot has its support only upon the flanges D, D, and the boutons c, c.
The proportion of the area of a cross section of the puncturing portion A to the
superficial area of the base of the sabot B is as one to two or thereabouts, or, in
other words, an area of a cross section of A is equal to one-half or about one-half of
the cross sectional area of B. This proportion outside the shape of the shot enables
me to utilize the impulse of the explosion of the powder on a given area, in driving
into an object a penetrating shot of a small area, and having correspondingly slight

page_text: resistance, so that I store up in the puncturing portion of the shot about twice the
penetrating capacity ever heretofore attained by a puncturing shot of equal cross
sectional area, except in sub-calibro projectiles.
The projectile being cast with the abrupt contraction, as shown at a', a¹, on the
line x, x, and with a concavity E in its base, the proportion of the thickness of the
metal from all to all is so arranged that about the instant of the impact of the
point of the shot against any resisting object the momentum of the heavy sabot B
will expend itself against the portion A as it enters the object struck by the
projectile and will be checked thereby, and the shock will break the said sabot
if the resisting object sufficiently impedes the shot's progress from the portion A,
leaving it in such a condition as to have the least possible resistance due to irregular
forms. In order that the sabot may break from the penetrating portion about the
time of impact, and yet receive the initial force of the explosion without frac-
turing the gun or injuring it, great care should be exercised with regard to the
thickness of metal a", all, which, in a solid shot, should be about one-half of the
short diameter of the puncturing portion. This precaution is necessary to avoid
any unequal tension in the shot, due to unequal cooling at the time of casting or
forging and thereby weakening it, and also to put such a thickness of metal on this
line as will make it sufficiently strong to safely receive upon its base the impulso
of the discharge.
د
This necessity has been proven by actual experiments with 15-inch projectiles and
smaller calibres fired from altered guns with two grooves, and it has been found
from experience that the best proportion for the thickness of the metal on the line
a to a in 15-inch solid projectiles is about 3%, inches, or as heretofore stated,
and is about the same proportion in projectiles of other calibres. The length of the
puncturing portion should be for projectiles to be used in altered smooth bore guns
from its tip to the sabot about equal to 11, times the diameter of the sabot, and
in guns cast for rifling the puncturing portion should be from 1%, times to twice
the diameter of the sabot. But it is necessary in all projectiles for altered guns to
have the distance from the centre of the boutons to the forward end of the flanges
at least equal to the diameter of the bore of the gun.`
It has also been ascertained by experiment that solid shots made, as shewn in
Figures 25, 26, 27, and 28, having gradually declining curves, combined with a deep
recess 2 in their butts, fail and break in the gun from the impulse of the discharge;
their weakness resulting from unequal tension caused by unequal cooling between
the inner and the outer curved lines. To overcome this difficulty, I cause these lines
to recedo more rapidly from cach other, and thereby obtain a shot so proportioned
that it will cool with sufficient uniformity to avoid unequal tension. Placing the
projectile in the muzzle of the gun with the flanges D', D¹, in the grooves, the pro-
jectile follows the grooves of the rifle while being forced home.
The distribution of the weight and the formation of this projectile are such as to
reduce to a minimum the force necessary to overcome the vis inertia of the shot in
commencing its rotation around its longest axis, for the reasons that the principal
weight of metal is located near the centre of the bore and is put in motion through
a smaller circumference than the lesser weight near the periphery. After its dis-
charge from the gun the projectile rotating at a high velocity, and owing to its
twisted formation, penetrates in the manner of a spiral drill or corkscrew.
Of late years the ogival point for projectiles has been considered as having the
greatest penetrating capacity, but experiments prove that my improved projectilo will,
with the same gun and half the amount of powder at short range (180 feet), perform
moro work in a more satisfactory manner in passing through 15 inches of rolled
iron than the ogival pointed shot. The shape of my projectile in its cutting and
puncturing point performs an important mechanical function in the accomplishment
of these important results. Taking an elevation of the narrower side of the sub-
calibre portion, the outlines conform to an ogival point upon a radius of about 12
diameter, while an elevation of the broader side of the sub-calibre portion shows
a curvature of a greatly increased diameter, the contracting or converging curves

page_text: forming the cutting edges, so that I combine in this improved point the puncturing
capacity of the ogival point with the cutting capacity due to the lenticular cross
sectional form, while the greater width strengthens and braces the ogival shaped
portion in the narrow part of the same.
The grooves b, b, around the sabot are perpendicular to the longitudinal axis of
the gun on the side next to the cartridge, and beviled on the side to the point of the
shot, the pitch being about one to three. These grooves act in retarding the rapid
escape of gas by the instantaneous creation of a series of eddies within them, and
these eddies in turn prevent a rapid escape of gas directly through the windage
space.
By actual experiments it has been discovered that certain limited modifications
are necessary to adapt the principle of my Invention to projectiles of different
calibres, and I will proceed to describe in detail the lines and proportions of certain
projectiles both solid and cored for various calibres and designs of guns as shown in
the Drawings.
Figures 1, 2, 3, show a solid 15-inch shot. Figures 4, 5, 6, show a cored shot of
the same calibre, the outer lines being on more gradual curves, as seen at i, i, to
enable the chamber H to be enlarged, and the lower base is slightly convex, as at J,
to strengthen the hollow shot against the concussion of the discharge. The thick-
ness of metal in the body of this shot is about the same as on the line a, a,
Figure 2, and continues so throughout its extent. Figures 7, 8, 9, show an 11-inch
solid shot, and as the calibre decreases slightly the curved lines a, a, are slightly
more graduated towards the point, and it has a concave base. Figures 10, 11, 12,
show an 11-inch cored shot having about the same outline as the solid shot of the
same calibre and a slightly convex base. Figures 13, 14, 15, show a 9-inch solid
shot built substantially on the proportions above named. Figures 16, 17, 18, show
a 9-inch cored shot formed upon the principle above stated. Figures 19, 20, 21,
shew a 7-inch solid projectile with curved lines p, p, slightly more graduated
towards the point. Figures 22, 23, 24, show a 7-inch cored shot formed on the
same principle, and Figures 25, 26, 27, and 28 show a shot so formed that it broke
in the gun. The cored shots have the bursting charge introduced through the
screw hole 7, which is stopped by a plug in the slightly convex butt, and the charge
may be exploded by either a time or percussion fuse, or by the heat of concussion.
When advisable I propose to introduce into the opening o a paper cased meal-
powder time fuse or a Boarman fuse.
Projectiles constructed as above described, when made for guns cast for rifling,
allow a great increase of distance between the points of support in the grooves,
they have a graceful appearance, a perfect tone in flight, a high initial velocity, an
extraordinary terminal velocity, a very low trajectory, and great precision. A
long, laborious, and expensive series of experiments has shown that with an altered
sinooth bore 15-inch cast-iron gun I am enabled with seventy pounds of Oriental
Mammoth powder, at short range (180 feet), to put a shot, such as shown in
Figures 1, 2, 3, weighing five hundred and thirty-two pounds, through fifteen
inches of rolled iron plates securely fastened together, and into thirteen feet nine
inches of hard gravel backing. I can also at long range (about one mile), with
a charge of seventy pounds of the same powder, put a like shot (532 lbs.) through
a target composed of rolled iron plates twelve inches in thickness, and into a very
hard clay and gravel bank to the distance of three feet.
I may chill the projectiles down to a slightly descending curved line from the
forward ends of the flanges, but prefer to throw a chill in the form of decreasing
steps down between the flanges, as shewn in Figure 1, for the reason that this
chill aids in cooling the thick part of the mitten-shaped portion, and thus pre-
vents unequal tension.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim-
First. A projectile having a sub-calibre puncturing portion of chilled cast iron

page_text: of a lenticular or other suitable cross sectional form, and a full calibre sabot cast
together, or in one piece, as above set forth and for the purpose specified.
Second. In combination with the base or sabot of the projectile 'the mitten-
shaped puncturing portion having its body twisted to conform to the pitch of the
rifling of the gun, as above set forth and for the purpose specified.
Third. The said mitten-shaped portion in combination with the flanges as above
described and for the purpose specified.
Fourth. The hollow mitten-shaped sub-calibre portion with or without the fuse
hole in combination with a full calibre sabot provided with an opening and plug,
as above set forth and for the purposes specified.
Fifth. In the aforesaid projectiles the grooves for retarding the flow of gas around
the windage space as above set forth.
Sixth. In projectiles for heavy ordnance the points cast with converging lines
to form a gradual contracting cutting point, as above set forth and for the purpose
specified.
.
Seventh. A centred projectile with windage and with its body twisted to
conform to the pitch of the rifling of a gun, and with a point of an ogival form
on one side, and the curvature of the point on the other side, of a greatly increased
diameter, and its general forin lenticular or oval in cross section, as abovo set forth
and for the purpose specified.
In witness whereof, I, the said William Robert Lako, have hereunto set my
hand and seal, this Seventh day of November, in the year of our Lord One
thousand eight hundred and seventy-six.
W. ROBT. LAKE. (L.S.)