CERTAIN IMPROVEMENTS IN FIRE-ARMS, ORDNANCE, AND PROJECTILES
Year: 1863

page_text: LETTERS PATENT to James Mackay, of Aigburth, in the County of
Lancaster, for the Invention of "CERTAIN IMPROVEMENTS IN FIRE-ARMS,
ORDNANCE, AND PROJECTILES."
i
COMPLETE SPECIFICATION filed by the said James Mackay at the
Office of the Commissioners of Patents, with his Petition and Decla
ration, on the 1st October 1863, pursuant to the 9th Section of the
Patent Law Amendment Act 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
MACKAY, of Aigburth, in the County of Lancaster, send greeting.
WHEREAS I am in possession of an Invention for "CERTAIN IMPROVE
MENTS IN FIRE-ARMS, ORDNANCE, AND PROJECTILES," and have petitioned Her
Majesty to grant unto me; my executors, administrators, and assigns, Her
Royal Letters Patent for the same, and have made solemn declaration that
I am the first and true Inventor thereof.
NOW KNOW YE, that I, the said James Mackay, do hereby declare that
the following Complete Specification, under my hand and seal, fully describes
and ascertains the nature of the said. Invention, and in what manner the
same is to be performed, in and by the following statement and accompanying
Drawings (that is to say) :-
The Invention relates, first, to the manufacture of ordnance, which may

page_text: also be practically applied to small arms, and is designed for the purpose of
discharging elongated projectiles from what is known as a "smooth-bore'
gun; and the improvements consist in the application and use of diagonal
grooves formed in the interior surface of the gun at a greater angle than
hitherto employed, which are to act as "windage" grooves, so that the powder
and gas passing down such grooves encircling the projectile shall have a
longer distance to travel than the projectile, and also to cause the projectile to
revolve round its longest axis at a high rotation as it passes down the
gun. The projectiles are not required to enter or fit these grooves as in
"rifles," but simply to pass down the smooth surface in which the grooves
are formed.
In the manufacture of the gun I pursue any of the ordinary methods
either as muzzle or breach-loader having smooth bores, and groove them in
the following manner :-Take, for instance, a smooth-bore sixty-eight pounder
is to be grooved at the angle marked A in the Diagram, Sheet 1, for which
the length of the projectile should be about twice the diameter of the bore,
but the angle of the groove is to be increased if a heavier projectile is
employed and decreased if a lighter one is used, by which means also the
necessary velocity, accuracy, and range is obtained. The Diagram, Fig. 3,
Sheet 1, having been properly tested on the small barrel A', I
propose to
extend the same rule or slight variation thereof to ordnance; shewing in the
Diagram the angle extended to the sixty-eight pounder. I would remark
that the aforesaid grooves may either be formed from end to end of the bore,
or only part way, and that the depth of the grooves may be increased as the
angle of the grooves increases, and lessened as it is diminished; the length of
the projectile may also be increased or diminished as the angle of the groove
is increased or diminished, Fig. 2 being about the minimum angle for a pro-
jectile of twice the length of the diameter of the bore.
The second part of the Invention relates to further improvements upon
projectiles described in the Specification of Letters Patent granted to ine,
dated the Sixteenth day of April, One thousand eight hundred and sixty-two,
No. 1101, in some of which a central channel was employed to give
windage," and to cause the projectile to strike "on end" when fired from a
smooth ungrooved bore.
66
The present Invention relates to modifications of projectiles as mentioned in
such Specification, and is designed to adapt the form and proportions of pro-
jectiles so as to cause them to strike the object "on end." The Invention
consists in balancing the projectiles either internally or externally in the
following manner :-The "blank" of steel or other sufficiently hard metal is

page_text: first to be turned in a lathe, or planed to fit the bore; it is then to be reduced
in length to the proportion as 9 is to 11, about which proportion should be
maintained either in large or small projectiles when fired from an ungrooved
smooth bore, or they may be fired from the ordinary rifled cannon when made
of this length. In this state it is to be balanced between points in the centre
of its length to insure accuracy, as shewn in Fig. 15 of the Drawings; when
this proportion is obtained, the front part of the projectile is to be turned to
any of the forms shewn in Figs. 1, 2, 3, 4, 5, Sheet 2; this end being so
finished, a corresponding weight is to be turned out or removed from the back
part of the projectile, which when finished and returned to the balance points,
will turn on the pins in a perfect balance as when the blank was first
balanced, and when fired from a smooth bore will be found to strike "on end"
at ranges corresponding with quantity and quality of gunpowder used. A
more economical method of finishing the projectiles may be adopted, as in
Fig. 15, wherein the two ends alone are polished. I would remark, also, that
when the projectiles are cast in a mould, I cast a tail or projecting piece to
one end thereof, by which the projectile is retained in the lathe when being
turned or polished, and which must be removed when the projectile is
finished. It is also to be observed that the moulds in which such castings
are made are to be formed so as to produce balanced projectiles, as before
described; it is preferred to polish all hardened steel projectiles when required
to enter metallic plates, or the projectile may be passed through dies by
bydraulic or other pressure to ensure a polished surface. When the grooved
bore is to be employed, the projectiles, as shewn in Figs. 6, 7, 8, 9, 10, 11,
12, 13, 14, 15, 16, 17, 18, 19, and 20, are preferred to be used, such pro-
jectiles being longer in proportion to their width than those hitherto described
for the smooth bore, which extra length and consequent weight can be used
by reason of the high rotatory motion given to the projectile by the grooves.
It has been found, from practical experiments, that the velocity of the pro-
jectile, and consequently the striking power, is greatly increased with the
same proportion of powder as used for the perfectly smooth bore by the use
of the grooves when combined with the method of loading, which I shall now
proceed to describe.
My Invention consists, lastly, in the use of wood, sawdust, cotton wool,
cotton wadding, tow, wool, or other elastic material to be placed between the
powder and projectile, which when the concussion of explosion occurs, causes
the projectile to become slightly and easily moved before the full power of
the powder acts upon it, which ensures the safety of the gun and diminishes
the recoil. The sawdust or cotton wadding is to be saturated with oleaginous

page_text: matter to give lubrication, and to prevent it from burning too rapidly, and
may be placed in the cartridge bag between the powder and the projectile, in
which instance a circular piece of pasteboard or other material is to be
inserted and used to keep them separate, or the wadding may be placed in a
separate bag, or the sawdust may be placed in the end of the bag and tied,
and the powder placed above it. The cartridge bag must be so mado as to
burst when the explosion takes place to allow the sawdust or wadding to
encompass the projectile, thus preventing the escape of the gas. By filling
the grooves, and allowing the projectile to receive the full force of the powder
without waste, or the cartridge itself containing the powder may also be made
of cotton wadding; this description of gun wadding may also be applied to
advantage in the ordinary smooth bore with spherical projectiles. It has been
found that numerous discharges may be effected in this manner without the
bore requiring cleaning.
In Sheet 1, Figs. 4, 5, and 6 represent three descriptions of projectiles
called shells, being balanced from the interior, as shewn, and from the
exterior the explosion of which may be effected by any ordinary time fuse, as
shewn, or by percussion; the cavity in the shells may be large or small
according to the amount of resistance and strength required to penetrate iron
plates.
In witness whereof, I have hereunto set my hand and seal, this 29th
1000