IMPROVEMENTS IN PROJECTILES AND IN CARTRIDGES
Year: 1866

page_text: LETTERS PATENT to Clinton Edgcumbe Brooman, of 166, Fleet Street,
in the City of London, for the Invention of "IMPROVEMENTS IN PROJECTILES
AND IN CARTRIDGES."-A communication from abroad by John Webster
Cochran, of New York, United States of America.
PROVISIONAL SPECIFICATION left by the said Clinton Edgcumbe Brooman
at the Office of the Commissioners of Patents, with his Petition, on the
21st March 1866.
I, CLINTON EDGCUMBE BROOMAN, of 166, Fleet Street, in the City of London,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN.
PROJECTILES AND IN CARTRIDGES," to be as follows :-
The first part of this Invention consists in a novel construction of the base
or rear part of elongated projectiles, and of the metal packing attached thereto,
and a novel mode of applying lubricating material in relation therewith,
whereby the rotation of the ball in its passage along the rifle grooves of the
gun is effectually insured with a lighter packing than has been commonly
employed, and the effective lubrication of the bore and grooves of the gun is
provided for. At a short distance from the base of the projectile there is in its
exterior a circumferential V-shaped groove, and from this groove to the base
there is a series of longitudinal grooves arranged so as to leave the inter-
vening fins or ribs alternately thicker and thinner. Around the faces of these
fins there is snugly fitted a band of copper or other comparatively soft but

page_text: tough metal, the front portion of which is contracted in conical form to fit the
rear part of the circumferential groove. This band leaves the longitudinal
grooves open at the base only. The V-shaped groove is fitted outside of the
conical portion of the band with cotton, hemp, or other fibrous material,
saturated with tallow or other suitable lubricating material, and outside of this
is wound one or more layers of copper wire, the outer surface of which is flush
with that of the projectile; this wire may be wound round the whole surface
of the band or only round the fibrous material which fills the V-shaped groove.
The thicker fins have in their faces shallow longitudinal grooves, into which
the band is depressed in order, 1st, that it may insure the turning of the
projectile with the band as the latter is caused to rotate by its movement in
the grooves of a rifled gun; and, 2nd, that it may expand to fit the bore
and grooves without being burst. When the powder is ignited, the gases
generated thereby enter the longitudinal grooves and expand the copper
band into close contact with the bore of the gun, and, into the rifle grooves, if
the gun be rifled, and at the same time acting against that part of the band
which is turned inwards over the fronts of the longitudinal grooves drive the
band forward, thereby causing the circumferential expansion of the fibrous,
material and its covering of copper wire and pressing out the wire against the
boro and into the rifled grooves. By these means all windage is prevented, and
the shot caused to receive a rotary motion from the rifle grooves, while the
lubricating matter being expelled from the fibrous material between the coils-
of wire by the forward pressure on the band, lubricates the bore.in advance of
the passage of the band. It will also be seen that those parts of the band
which are pressed into the shallow grooves in the thicker fins of the shot will
yield somewhat to the force exerted by the explosion of the powder, and allow
the band to expand as aforesaid without danger of tearing or bursting tho
same, which would be likely to occur if the expansive force of the powder was
exerted upon a band formed in a true circle, which could not expand except
by the stretching of the metal. The wire not only protects the fibrous material
from being torn by the edge of the grooves of a rifled gun, but also assists the
band in producing the rotary motion. The shallow grooves and corresponding
depressions in the band are of such depth that the limited expansion necessary
to make the band fit the bore and grooves will not withdraw the depressions
from the necessary hold upon one side of each groove to insure the rotation of
the projectile.
The second part of this Invention relates to cartridges for breech-loading
and -revolving arms. Cartridges in common use have the fulminate priming
contained in a hollow rim or flange formed around the rear end or bottom of

page_text: the case or shell; this arrangement of the priming has serious defects, the
principal of which are, 1st, the danger of explosion by a blow on the pro-
jecting rim or flange, or by dropping the cartridge on any hard surface; 2nd,
the large quantity of priming required to extend all around the rim or flange;
3rd, the uncertainty of a uniform distribution of the fulminate around the
rim; and, 4th, the deterioration to which the priming is subject by remaining
for a considerable length of time in contact with the gunpowder.
Various attempts have been made to obviate these defects by the arrange-
ment of the fulminate in the centre of the bottom of the case; but these
central-fire cartridges have an open vent hole between the fuminate and the
gunpowder, by which the fulminate is liable to the same deterioration as that
of a percussion cap left on the nipple or cone of a loaded fire-arm.
This part of the present Invention consists in a novel arrangement of and mode
of securing the fulminate, whereby it is protected from accidental explosion; a
small quantity is made to serve the purpose; its uniform distribution over all
parts of the cartridge upon which the hammer or firing pin can strike is insured,
and its perfect'isolation from the gunpowder is obtained. I take a cartridge case
having at its base a projecting rim resembling that of the rim fire cartridge,
except that the rim is closed up or made without the cavity usually provided for
the reception of the fulminate priming. I insert into the open end of the case
and push it down to the base a priming disc or ring of suitable metal and of
sufficient thickness in a direction parallel with its axis to resist the blow of the
hammer without bending, and of a diameter to fit the interior of the case.
This disc or ring has its rear face flat or of a form to fit against the bottom of
the shell, except that there is provided in it an annular concentric groove for
the reception of the fulminate. The disc. or ring may have a large central
opening, or a small central orifice or vent. The latter form admits of the
annular groove being made of smaller circumference, so that it requires a
smaller quantity of fulminate to fill it. The fulminate priming is inserted into
and uniformly all round the groove of the disc or ring before inserting the
latter into the cartridge case by means of a brush, or in any other suitable
manner, and the rear face of the said disc or ring is afterwards varnished in a
similar manner to a percussion cap to protect the fulminate. The disc or ring
is secured at the bottom of the case by indenting or contracting the case all
around, or at two or more points in its circumference immediately in front of
it. The case is afterwards charged with gunpowder. The hammer or striker
of the fire-arm is constructed with a point, and arranged to strike the bottom
of the case.opposite the groove, and when the fulminate is thereby exploded

page_text: it passes the disc forward sufficiently for its fire to pass between the bottom
of the case and the part of the rear face of the disc or ring, and so reach
the gunpowder through the central opening or orifice through which there
has been no communication between the fulminate and the gunpowder
until the fulminate has been exploded, the communication having been pre-
viously closed by the portion of the rear face of the disc immediately surrounding
the opening or orifice fitting closely against the bottom of the shell.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Clinton Edgcumbe Brooman in the Great Seal Patent Office
on the 20th September 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CLINTON
EDGCUMBE BROOMAN, of 166, Fleet Street, in the City of London, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of March, in the year of our Lord
One thousand eight hundred and sixty-six, in the twenty-ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said-Clinton Edgcumbe Brooman, Her special licence that I, the said Clinton
Edgcumbe Brooman, my executors, administrators, and assigns, or such others
as I, the said Clinton Edgcumbe Brooman, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time and
int all times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention for
* IMPROVEMENTS IN PROJECTILES AND IN CARTRIDGES," (communicated to me
from abroad by John Webster Cochran, of New York, United States of
America,) upon the condition (amongst others) that I, the said Clinton
Edgcumbe Brooman, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said Clinton Edgcumbe Brooman, do hereby
declare the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the

page_text: following statements thereof, reference being had to the Drawings hereunto
annexed, that is to say:-
The first part of this Invention consists in a novel construction of the base
or rear part of elongated projectiles, and of the metal packing attached
thereto, and a novel mode of applying lubricating material in relation there-
with, whereby the rotation of the ball in its passage along the rifle grooves of
the gun is effectually insured with a lighter packing than has been commonly
employed, and the effective lubrication of the bore and grooves of the gun is
provided for.
:
Figure 1 of the accompanying Drawings is a side view, Figure 2 a central
longitudinal section, and Figure 3 a view of the rear end of a projectile con-
structed according to this Invention.
At a short distance from the base of the projectile A there is in its exterior
a circumferential V-shaped groove m, and from this groove to the base there
is a series of longitudinal grooves a, a, arranged so as to leave the intervening
fins or ribs d and e alternately thicker and thiuner. Around the faces of
these fins d and there is snugly fitted a band 6 of copper or other com-
paratively soft but tough metal, the front portion of which is contracted in
conical form to fit the rear part of the circumferential groove, as shown
at i, i, Figure 2; this band leaves the longitudinal grooves a, a, open at the
base only. The V-shaped groove m is fitted outside of the conical portion i
of the band with cotton, hemp, or other fibrous material saturated with tallow
or other suitable lubricating material, and outside of this is wound one or
more layers of copper wire g, the outer surface of which is flush with that of
the projectile; this wire may be wound round the whole surface of the band,
or only round the fibrous material which fills the V-shaped groove.
The thicker fins d, d, have in their faces shallow longitudinal grooves c, c,
into which the band 6 is depressed, in order, 1st, that it may insure the
turning of the projectile with the band as the latter is caused to rotate by it's
movement in the grooves of a rifled gun; and, 2nd, that it may expand to
fit the bore and grooves without being burst. When the powder is ignited
the gases generated thereby enter the longitudinal grooves a and expand the
copper band into close contact with the bore of the gun and into the rifle
grooves if the gun be rifled, and at the same time acting against that part of
the band which is turned inward over the fronts of the longitudinal grooves
a, a, drive the band forward, thereby causing the circumferential expansion of
the fibrous material f and its covering of copper wire, and pressing out the
wire against the bore and into the rifle grooves. By these means all windagė
is prevented and the shot caused to receive a rotary motion from.the rifle

page_text: grooves, while the lubricating matter being expelled from the fibrous
material between the coils of wire by the forward pressure on the band lubri
cates the bore in advance of the passage of the band b. It will also be seen
that those parts of the band 6 which are pressed into the shallow grooves cin
the thicker fins d, d, of the shot will yield somewhat to the force exerted by the
explosion of the powder, and allow the band 6 to expand, as aforesaid, without
danger of tearing or bursting the same, which would be likely to occur if the
expansive force of the powder was exerted upon a band formed in a true
circle which could not expand except by the stretching of the metal, The
copper wire g not only protects the fibrous material from being torn by the
edge of the grooves of a rifled gun, but also assists the band 6 in producing
the rotary motion. The shallow grooves and corresponding depressions in the
band are of such depth that the limited expansion necessary to make the band
. fit the bore and grooves 'will not withdraw the depressions from the necessary
hold upon one side of each groove to insure the rotation of the projectile.
I claim, under this part of the Invention, as the improvements in projectiles,
1st, the band b, saturated fibrous material f, and coiled wire g in combination
with each other, and with the circumferential and longitudinal grooves in tho
projectile, substantially as and for the purpose. herein-before described and
represented in the accompanying Drawings; and, 2nd, the grooves c, c,
arranged with reference to the grooves a, a, and m, for the reception of depres
sions of the expanding band, as and for the purpose herein-before described
and represented in the accompanying Drawings.
.
The second part of this Invention relates to cartridges for breech-loading
and revolving arms. Cartridges in common use have the fulminate priming
contained in a hollow rim or flange formed around the rear end or bottom of
the case or shell. This arrangement of the priming has serious defects, tho
principal of which are, 1st, the danger of explosion by a blow on the pro-
jecting rim or flange, or by dropping the cartridge on any hard surface;
2nd, the large quantity of priming required to extend all around the rim or
flange; 3rd, the uncertainty of a uniform distribution of the fulminate around
the rim; and, 4th, the deterioration to which the priming is subject by
remaining for a considerable length of time in contact with the gunpowder.
Various attempts have been made to obviate these defects by the arrange-
ment of the fulminate in the centre of the bottom of the case, but these
central-fire cartridges have an open vent hole between the fulminate and the
gunpowder by which the fulminate is liable to the same deterioration as that
of a percussion cap left on the nipple or cone of a loaded fire-arm.
This part of the present Invention consists in a novel arrangement of, and

page_text: mode of securing the fulminate, whereby it is protected from accidental
explosion; a small quantity is made to serve the purpose, its uniform dis-
tribution over all parts of the cartridge upon which the hammer or firing pin
can strike is insured, and its perfect isolation from the gunpowder is
obtained.
Figure 4 is a central longitudinal section, on an enlarged scale, of a car-..
tridge case constructed according to this Invention; Figure 5 is a back view
of the priming disc or ring; Figure 6 is a back view of a priming disc of
modified form.
I take a cartridge case A; having at its base a projecting rim a resembling
that of the rim fire cartridge, except that the rim is closed up or made
without the cavity usually provided for the reception of the fulminate priming.
I insert into the open end of the case and push it down to the base a priming
disc or ring B of suitable metal and of sufficient thickness in a direction
parallel with its axis to resist the blow of the hammer without bending, and
of a diameter to fit the interior of the case A. This disc or ring has its rear
face flat or of a form to fit against the bottom of the shell, except that there
is provided in it an annular concentric groove c for the reception of the
fulminate.
:
The dise or ring represented in Figures 4 and 5 partakes more of the
character of a ring having a large central opening 6, but that represented in
Figure 6 is more strictly speaking a disc having only a small central orifice or
vente; the latter form admits of the annular groove c being made of smaller
circumference, so that it requires a smaller quantity of fulminate to fill it.
The fulminate priming is inserted into and uniformly all round the groove c
of the disc or ring, before inserting the latter into the cartridge case, by
means of a brush or in any other suitable manner, and the rear face of the
said disc or ring is afterwards varnished in a similar manner to a percussion
cap to protect the fulminate. The disc or ring secured at the bottom of the
case by indenting or contracting the case all around or at two or more points
in its circumference immediately in front of it in the manner shown at
d, d, Figure 4; the case is afterwards charged with gunpowder.
The quantity of priming required to fill the groove c is much less than the
quantity required in a rim fire cartridge, and when the disc is made with a
mere vente in the centre and a groove of small circumference, need not be
one-fourth of the latter quantity. It is perfectly isolated from the gunpowder
by the disc or ring fitting tight against the bottom of the case, and is, more-
over, so protected by the disc or ring and the bottom of the cartridge case as
to be safe from accidental explosion, as no blow but that produced by a hard

page_text: point striking the bottom of the cartridge case directly opposite. the groove c
can ignite it.
The hammer or striker of the fire-arm. is constructed with a point, and
arranged to strike the bottom of the case opposite the groove, and when the
fulminate is thereby exploded it presses the disc forward sufficiently for its "
fire to pass between the bottom of the case and the part of the rear face of
the disc or ring, and so reach the gunpowder through the central opening or
orifice 6 or e, through which there has been no communication between the
fulminate and the gunpowder until the fulminate has been exploded, the com-
munication having been previously closed by the portion of the rear face of 1
the disc immediately surrounding, the opening or orifice fitting closely against
the bottom of the case.
I claim, under this part of the Invention, as the improvements in
cartridges, the disc or ring B with an annular groove in its rear surface
containing the fulminate priming fitted and secured in the bottom of the 1
case of the cartridge, substantially as herein-before described, whereby the
fulminate is perfectly isolated from the gunpowder until the explosion of the
fulminate takes place.
In witnes whereof, I, the said Clinton Edgcumbe Brooman, have
⚫ hereunto sot my hand and seal, this Twentieth day of September, One 2
thousand eight hundred and sixty-six.