The Sun.
London, England, 1855-08-23 00:00:00

BRITTKN'S IMPROVED SHELLS.

Further experiments were made yesterday at Shoe-
huryness, under the direction of Lieut.-Colonel Mitchell,
Royal Artillery, with the new shells invented by Mr,

Bashley Britten. It will be remembered that, according
to the official return published, these projectiles when
last tried acquired an effective range of about 1,000 prds
more than the service solid shot, and this with little
more than half the charges of powder. Since that period
the inventor has slightly altered the form of the hinder
part of his shells, conceivinit.that this would still fur-
they increase their range. His expectations, however,

have not been fulfilled in that respect. and yesterday the
new shells, though they maintained their superiority as
rewards the service shot, fell short of the range last ob-
tained by about 400 or 500 yards. Of course the best
possible form is not to be arrived at all at once, and in
this instance experience seems to teach that the shape
of the shell used on the 26th ult. is best adapted to in-
sure both extent of range and accuracy of aim. In any
case there now appears no reason to doubt the soundness
of the principle. Mr. Britten claims for his projectiles
the power of the Lancaster shells, with far greater accu-
racy of flight and with a very trifling increase of cost, if
any, over the ordinary service shot. Of seven experi-
mental shells fired yesterday six were projected from a
rifled 9-pounder, the object being to carry out the
principle of the Minii rifle, and to procure for the shot
the rotatory motion. Whether this motion is or is not
secured seems to be a moot point, but that the grooves
exert some influence would certainly appear to be shown
by the fact that the only experimental shell fired from a
smooth bore was a failure. The longest flight taken by
the new shell yesterday was 3,150 yards, which repre-
soots the first graze, not the extreme range; this was at
an elevation of 11i degrees, with a powder charge of lilb.
At the same elevation, and with a 31b. charge of powder,
the service shot fell short of this range by some 600
yards. One noticeable feature with regard to the ex-
perimental shot was that the increase of the charge from
lilb. to 21b., instead of adding to the range diminished
it. Then, again, their conical shape allows of a greater
weight in the Britten shells as compared with the ser-
vice shot when firing from guns of the same calibre.
The weight of the experimental shot fired from the
9-pounder was 141 b. yet the charge of powder used was
lilb. as against 31b. for the service ball of less weight.
The advantages thus gained are apparent. By adopting
these projectiles a 9-pounder gun is virtually converted
into a 14-pounder, and so with cannon of greater
calibre. The strain upon the gun, also, is of course con-
siderably less owing to the diminished charges required.
There is another point „in connection with this inven-
tion which deserves considbratton. ' An insuperable
difficulty has hitherto been experienced in so coating
the body of an iron projectile with soft metal at
its hinder part that it shall expand and fill the
bore of the gun when fired, in order to pre-
vent what is technically known as " windage," and,
by adapting itself to the grooves in its passage, to give
the ball a rotatory motion. Previously to this invention,
it had not been found possible to render the union of
the iron and the lead, or softer metal, so complete that
the latter would stand the explosive force of the powder.
Mr. Britten, however, has overcome this difficulty, and
has thus reduced the "windage," or waste of projecting
power, to, perhaps, the lowest possible amount. Inde-
pendently of the rotatory motion, if that be gained, the
filling up of the bore in this way so steadies the ball that
it is not forced violently at, nay one point against the
sides of the gun, and the pressure being equal throughout
this constant cause of wear and tear in our present ar-
tillery is avoided. By the conical form of the new shell
the amount of atmospheric resistance is, of course, con-
siderably reduced as compared with spherical shot, and
the centre of gravity is so placed that the missile flies
with its point always in advance. It may thus be made
to explode on striking in the same mariner as the Lan-
caster shells, or it may be used, as was the case yester-
day, without being charged with powder t all.
The experiments were made at di.4erent degrees of
elevation, but with only one description of shell—the
9 pounder being the on,ly rifled gun yet adapted for
practice with these projectiles. It seems very desir-
able that they should- be tested as soon as possible
with guns of a larger calibre. If the principle is
good for anything no time should be lost in applying
it—at least this is the conclusion which presents itself to
unofficial minds ; and an invention which promises to
add even half a mile to the range of our artillery may be
thought worth trying on a large scale. The inventor
however, has not much to cheer him in his past attempts
to improve the science of gunnery. He has already,
stated in his published letters that " the proper officers,
to whom his plan was first referred, looked upon ft as
not appearing of sufficient advantage to the service to
call for further consideration, and to this may b• added
Mr. Monsell's admission that the invention has alre. 849.
been nine months before the Government. Then no
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