IMPROVE- MENTS IN THE MANUFACTURE OF PROJECTILES FOR BREECH LOADING RIFLED ORDNANCE
Year: 1882

page_text: LETTERS PATENT to Josiah Vavasseur of the London Ordnance Works Bear
Lane Southwark in the County of Surrey for an invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF PROJECTILES FOR BREECH LOADING RIFLED
ORDNANCE."
**
PROVISIONAL SPECIFICATION left by the said Josiah Vavasseur at the
Office of the Commissioners of Patents on the 1st April 1882.
JOSIAH VAVASSEUR of the London Ordnance Works Bear Lane Southwark in
the County of Surrey "IMPROVEMENTS IN THE MANUFACTURE OF PROJECTILES
FOR BREECH LOADING RIFLED ORDNANCE,"
This Invention has for its object improvements in the manufacture of projectilės
for breech loading rifled ordnance.
1
In the Specification of a former Patent granted to me No 1521 in the year 1874
I described the securing of solid bands or rings of copper or other suitable metal
around the circumference of projectiles by inserting the bands or rings into grooves
formed to receive them.
Instead of thus inserting a band or ring into a groove cut around the circum-
ference of the projectile I now propose to form the projectile with an abutment to
come against the rear end of the ring and with no abutment in front of the ring
and around the circumference of that part of the projectile which is to be embraced
by the ring and which is just in front of the abutment I form numerous grooves
notches or indentations either longitudinally circumferentially or both to prevent
the ring turning or moving on the projectile.
In the case of chilled projectiles or those made of very hard metal they may be
cast with these grooves notches or indentations shaped.or formed in them or this
part of the circumference of the projectile may be cast or made in form of a
polygon and the rear abutment only will require to be turned ground. or
otherwise made approximately true for the band to bear against, the projectiles

page_text: can in consequence be made at less cost and they will not be weakened by the
removal of the skin of the casting as is the case when the grooves are cut in.
As described in the Specification above referred to the bands when put into
place upon the projectile are reduced in diameter by being forced through conical
dies or by other suitable means made to fit closely the part of the projectile
prepared for them and to enter into the grooves notches or indentations already
referred to sufficient grip is thus obtained to enable the band to rotate the projectile
when fired from a breech loading gun suitably rifled.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Josiah Vavasseur in the Great Seal Patent Office on the 29th September
1882.
JOSIAH VAVASSEUR of the London Ordnance Works Bear Lane Southwark in
the County of Surrey-" IMPROVEMENTS IN THE MANUFACTURE OF PROJECTILES
FOR BREECH LOADING RIFLED ORDNANCE
"
This Invention has for its object improvements in the manufacture of projectiles
for breech loading rifled ordnance.
In the Specification of a former Patent granted to me No 1521 in the year 1874
I described the securing of solid bands or rings of copper or other suitable metal
around the circumference of projectiles by inserting the bands or rings into grooves
formed to receive them.
The bands or rings were reduced in diameter and made to fit into the grooves
by forcing the projectiles with the rings surrounding them through dies.
When the rings are all cut accurately, to size and the grooves around the
projectiles all turned accurately to form no difficulty is experienced in securing the
rings into the grooves in the above manner. In the manufacture however of
chilled iron projectiles and all projectiles cast to form the grooves if cast in are
irregular in dimensions and no such uniformity in diameter and width of groove
can be obtained as when the grooves are cut in-If the grooves are cut in the
strength of the projectiles is materially reduced by the removal of the skin. If
the grooves are cast in and consequently irregular the rings which are all of one
uniform size will have to be put into grooves of varying widths and depths and
the distance between the bottom of the groove and the inner circumference of the
die through which the projectile and the ring surrounding it have to be passed will
vary with the irregularity in the depth of the groove. If the groove is to deep
(that is if the diameter of the projectile at the bottom of the groove is to small)
there may not be sufficient metal in the ring to fill the space between the bottom
of the groove and the die and the ring will not be made to grip the projectile with
sufficient firmness consequently the ring will be loose and will have to be cut off
and another and thicker one put on its place. If on the other hand the groove is
shallow (that is if the diameter of the projectile at the bottom of the groove is too

page_text: great) there is more metal in the ring than is required and the excess as it passes
through the die after filling up the space between the bottom of the groove and the
die puts such a stress upon the base of the projectile that the projectile is
frequently fractured or, if not, the inetal of the projectile is left in such a state of
tension that when fired in the gun the base of the projectile comes off.
With chilled iron projectiles in which the tensile strength of the metal is very
low, there is a source of great danger.
To remedy these evils I now form the projectile with an abutment to come
against the rear end only of the ring and with no abutment in front of the ring-
and around the circumference of that part of the projectile which is to be embraced
by the ring and which is just in front of the abutment, I form numerous grooves
notches or indentations either longitudinally circumferentially or both or make it
of a polygonal form to prevent the ring turning or moving forward on the
projectile.
In this way when a copper ring is drawn down onto the projectile in front of
the abutment the ring can be made to grip closely the part of the projectile to
receive it and to enter the grooves notches or indentations formed therein even
though it be irregular in size whilst any excess of metal will only make the ring
of greater width without putting strain upon the projectile tending to break off
its base. Chilled projectiles or those made of very hard metal which have been
cast to form may consequently have bands of copper fixed around them without the
projectiles being weakened by the removal of the skin of the casting and in
addition the projectiles can be made at less cost.
In order that my invention may be fully understood I have shewn in the
Drawings hereunto annexed examples of projectiles having a copper band secured
around them in the manner above described.
Figure 1 is a side elevation of the two ends of a projectile with a portion of the
copper band cut away. Figure 2 is a cross section of the same taken on the
line x. y. Figure 1.
The back end of the head of the projectile where it joins onto the cylindrical
part or body of the projectile is made of some what larger diameter than the
remainder of the body so that it may just fit easily within the bore of the gun.
The rear end of the body of the projectile has also formed around it a projecting
flange to form the abutment for the copper band.
A is the copper band-B is the abutment in rear of the band. C are grooves or
notches formed in that part of the circumference of the projectile which is to be
embraced by the band. The body of the projectile may be solid or hollow as a
shell and as before stated it may be cast with the grooves or notches C formed
in it.
To fix the copper band around the projectile I preferably proceed as follows.
The ring or band is at first of a diameter large enough for it to be slipped over
either end of the projectile-the diameter of the ring on that side of it which is
towards the abutment on the projectile is then made of less diameter than the
abutment by forcing it for a certain distance into a properly prepared conical die.
The opposite side of the ring is now inserted into the tapered mouth of a suitable
die and the projectile and ring are together forced through this die which may
either be of a diameter to at once reduce the band to the required size and to
make it grip the projectile with sufficient firmness or it may be passed through
two or more dies in succession to reduce it gradually to the size required.-In this
way not only is the band reduced to the required size but the metal on the inner
surface of the band is squeezed into the grooves or notches C on the projectile
whereby the band is held securely in its proper place. When the band has thus
been fixed around the projectile it is turned in a lathe or other suitable machine to
the required profile and again passed through a suitable die to ensure absolute
uniformity in the external diameter of the ring.
It is not necessary that the whole of the body of the projectile between the band
and the head should be reduced in diameter to the extent shewn at Figure 1 it is

page_text: sufficient if a short length only of the body is thus reduced just in front of the band
as shewn at Figure 3 preferably however I form the projectiles in the way shewn
at Figure 1.
Having thus described the nature of my invention and the manner of performing
the same I would have.it understood that I claim :-
The manufacture of 'a projectile with a projecting flange or abutment B around
its base and a grooved or roughened surface C in front of the abutment and a
band A of copper or other suitable ductile metal drawn down over this roughened
surface so that its rear end shall bear against the abutment B whilst the forward
end has no abutment to bear against substantially as described.
In witness whereof I the said Josiah Vavasseur have hereunto set my hand
and seal this twenty seventh day of September in the year of our Lord
One thousand 'eight hundred and 'eiglity two.