'The views and opinions of Brigadier General John Jacob, CB. Aide-decamp to the Queen; Aide-de-camp to the Governor General of India, &c. &c. &c.; late commanding in chief the British forces in Persia; at present commanding the Sind Irregular Horse, and Political Superintendent of the North-West frontier of Sind.' [‎261] (291/481)

261
EXPLANATION OF THE DIFFERENCE BETWEEN THE
MINIE AND JACOB RIFLE BALL.
The Enfield rifle is peculiarly adapted for use with the
Minie ball, with which it performs well up to 800 yards.
But the very peculiarities which make the Enfield rifle
answer perfectly for the Minie projectiles quite unfit it
for use with mine. Let us consider what these peculiari
ties are.
The Minie ball possesses in itself the tendency to keep
its proper end foremost in its flight; it therefore requires
very little twist to keep it in the right path.
The^ large hollow in its hinder end makes it comparatively
light in proportion to its diameter; a less charge, therefore,
of powder is required to give it the same initial velocity, as
one of my projectiles of like calibre. Again, the hollow in
the Minie ball renders it liable to be blown into a tube if
much projectile force be suddenly applied to it.
For this ball, therefore, a thin barrel only is necessary,
and the grooves may be shallow, and have but very little
twist. At the same time, in order to get as much projectile
force to act on the ball as it will bear without injury, it is
requisite to lengthen the barrel, so as to make the power
act for as long a time as possible on the ball; while it is
actually found that an inferior description of powder (that
is, a slow burning powder) is the best for the Minie ball
and Enfield rifle. The Minie ball will not stand a great
force acting with great velocity on it—the lead gives away
under the shock ; wherefore it is necessary to impress this
ball with a more feehle force, acting for a longer time on it,
in order to produce an adequate projectile effect.
Well, then, the long weak barrel, with very little twist in
the grooves, answers admirably to fulfil the conditions
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