The Helena independent. [volume] (Helena, Mont.) 1875-1943, 1891-02-14
GREAT GUNS.
Monster Isuilt-Up Steel Rihed Guns To-
the Navy.

Monster BuiIt-Up Steel Rihed Gun for
the Navy.
WASHINGTON. Feb. 13.-The chief of the
ordnance bureau Of the navy department
has had published. for the use Of the service.
a table giving complete and accurate details
of all the built-up steel rifed guns for the
navy. This table is chiefly valuable to
ordnance experts and officers OF the ships
on which the various guns are mounted, but
there is much in it Of general interest. rs it
exhibits in u very graphic manner the ad-
vance made by the ordnance bureau since
the construction of guns Of this character
was fret undertaken. -
This improvement has been particularly
noticeable in the six-inch guns. The first
of this cslibre, officially known as SIX
inch B. L. r.. Mark H." weighed IS tons,
with a total length of 1873 feet, a total
length of bore of 176 inches. and & length
Of riaing Of 1866 inches. This gun, with
o service charge of fifty pounds OF powder,
WAS capable Of giving an initial velocity Of
2,OJO feet Der second to the 1OO-pound pro
jectile. giving it a striking energy at the
muzzle Of 2.773 foot-tons.
The next improvement was the Mark II.
gun, in which the same results we're obtained
from forty-fve to ~forty-eight pounds of
powder as with fifty pounds in the first gun.
The weight Of this gun vas increased me,
feet, with a bore 1s0.GS inches long and
1A.S5 inches OF riiing.
The next gun was the Mark Ill, of thirty
caliber length, in which, although the gun
was heightened. together with the bore and
the rifing. the weight WAS reduced to the
length, together with an improvement
in rifinR. enabled the same initial
results to be obtained with the charge OF
powder still further reduced to from forty
TOT to forty-seyen pounds. This is the
thirty-caliber six inch gun carried by most
of the new cruisers, and it il probably az
nearly perfection as could be reached in a
gun OF thirty calibers length.
Since then, however, guns Of thirty-iye
caliDers, or Il total length Of 1873 feet, and
corresponding increase in tho length OF bore
n riding have been made, giving, witt
the same charge as the perfected thirty
caliber gun. an initial velocity of 2,OsO fee
foot-tonA. IL was one of these guns tina
gave such excellent results at the Annapolis
armor test. in September.
Tho six-inch gun turned out in tn
future will be even better than this, beinl
forty calibres in length, or 21.3 feet over all
give all initial velocity of 2,rO feet pc
second and u muzzIe energy of 1924 foo
tons. This Improvement can best b
appreciated when it is said a shot from tn
thirty-caIibre euns could penetrate 10.2
Inches Of steel at the muzzIc, while on
from ths thirty-fye-caljbre gnn could pene
trate 1919 inches. and the forty-caiibr
11.3S inches. Similar improvements can b
traced in the eight and ten inch guns.
The most remarkable results are obtsine
with the fye-inch rapid-fire guns. weighin
three and one-tenth tons, with u totf
length of ia feet. This gun. with a SCI
vice charge of twenty-eight to thirt
pounds OF powder, will give to its fifty
pound projectile al initial velocity of 2.,5
feet per second, Il striking energy of LIE
foot tons, and q penetration Of nine inche
of steel.
The largest gun at present contemplate
by the bureau are the tbirteen-inch gun
for the new battle ships. They will weig
fO.05 tons, with Il total length Of fort
feet. The projectiIe will weigh liz
pounds. and will be impelled by
charge of 80 pounds of powder. I'll
velocity will be 2. 100 feet per second. an
the 0 striking energy of 1851 foot
tons will be attained. giving a penetratio
Of W.6G inches of solid steel. This gun wi
be capable, under favorable con Iitions, +,
piercing the heaviest armor afioat in AZ
navy, and the explosion of one of its emo
nous shells below the water line wou,
probably disable any ship in existence.