Evening star. [volume] (Washington, D.C.) 1854-1972, 1907-01-31
TIE LIFE Of BIG GUNS
.Twelve-Inch Pieces Can Be
Fired Only About Sixty Times.
RIFLInG is. THEN WORN OUT
Pieces Of Ordnance Of Greater Caliber
Now Proposed.
MAY USE HEAVIER PR0JECTILE
Gen. crozier Says That Our Coasts Are
as Well Fortified as Those Of Any
Nation in the Worll.
MAY USE HEAVIER PRoJECT1LE
BY WILLIAM e. CURTIS.

By WILLIAM r. CURTIS
Written for The Star and the Chicago Record
Herald.
Gen. William Crozier, chief Of ordnance
of the United States army, told me the
| other day that our big twelve-inch guns,
which carry projectile weighing thou
! sand pounds, with velocity of 1900 feet
q second, for several miles, can be fred
| only sixty or sixty-five times. After that
number of rounds the rif1ing in the bore of
| the gun. will become obliterated. There Is
difference of opinion as to what causes
this; whether the contact with the pro-
| jectile wears it out, or whether the intense
| heat, caused by the combustion of a large
| charge of powder, brings the skin Of the
| metal nearly to the melting point, and.
| being in that state, the rifling is washed
away by the rush of the powder itself. But
anyway, after sixty rounds, the projectile
| will not follow the rif1ng in the gun unless
/ a larger band of copper than usual is
| placed around it. The projectile is made of
steel and is embraced by a copper band
which, fitting into the rif1ing in the bore of
| the gun, causes its revolution. By enlarg-
| ing this band the gun may be made to last
a little longer. 1t can be fired perhaps a
| dozen times more.
mo, the quality of the steel in the gun
| is not impaired by its discharge" contin-
ued Gen. Crozier. 1T does not disintegrate
and the tension is not affected. AS gun Is
capable of being fired at the rate of forty
| five rounds an hour, You will see that the
| limit Of its life could be reached in a bat
| tie Of less than an hour and a half. Ac-
| cording to our calculations, the time that
| an ordinary fleet would require to pass the
| Notifications guarding the entrance of
| harbor, from the instant the first vessel
would come within range until the last
| vessel passed out of range, would be about
| two hours. 1t is, therefore, evident that
| 10yxy lyn1y faHh r1fflt0 cod to tic
| capacity upon that fleet, would not last
| through the engagement, and the same may
be said with regard to guns of smaller
| caliber, although, as the caliber dimin-
| ishes, the admissible velocity increases. A
six-inch gun, firing a projectile weighing
| 100 pounds with a velocity Of 1900 feet a
| second, can be fired twice many times as
a twelve-inch gun, and. If utilized to its full
| capacity during the attack of a fleet, 1t
| would last about hour and a quarter
This, you must appreciate, is very
| serious problem and has attracted a great
| deal of attention among all military ma
| tons.
| Progress Of Gun Construction.
"since the beginning of gun construction
| the art has at various times encountered
| elements of doubt which, for the time
| being, have placed a limit upon it's adj
| vance. For a long time the element of
doubt was the strength Of the guns to resist
| bursting, the powder n use being capable
| or developing nlSner pressure tndn the
guns could be made to Withstand, and the
charges therefore being necessarily kept
within small limits and giving correspond
| ingly low velocities to comparatively light
projectiles. There was gradual improve
ment in the methods of construction by the
use of better materials, by improved
! methods Of casting iron guns, by reinforce
ment with wrought-iron jackets, and
| finally, by introduction of the present high
class of steel forgings and the system of
building up of concentric cylinders under
shrinkage. These advances were accom-
panied by improvements in the powder
whereby its rate of burning was better con-
trolled and larger charges were employed,
which, giving off their gases more grad
ually, would sustain for longer period the
pressures which the guns. would endure
and would thus continue the accelerating
action upon the projectile.
1.-The improvement in powders naturally
brought about both the carrying forward
toward the muzzle Of the strong section of
the gun and the lengthening Of it SO as to
hold the projectile longer subject to the
accelerating force. These advances brought
about temporary check in regard to the
projectiles, perhaps more feared than real
lied, these being apparently unable to
withstand the impact produced by their
high velocities against first-class armor.
But such improvement of them was speed
| lily made as to remove this limit upon the
power of guns"
Lowering the Velocity.
"By lowering the velocity of a gun its
smaller charge and to come down from
2,6OO feet per second to $3.50 or 1900 feet.
By that means the life of the gun may be
prolonged at least 800 per cent. That is. by
using a smaller charge a 12-inch gun can
| be fired $50 times and 6-inch gun $50
times
'aThe ability to penetrate the armor of the
enemy's vessels is. of course, reduced by
| this process. A projectile weighing LOCO
pounds should pierce ten and half inches
| Of armor at a range of 10000 yards, or be-
tween five and six miles II fired at velec-
| ity of $500 feet per second. If this veloc-
| ity is reduced to 1900 feet the projectiie
would not go through more than nine
inches of armor. All this has to be con-
sidered. and the question of economy comes
| in also. A Pinch gun costs from $4,000
| to $4,000; cast-iron projectile weighing
| 1000 pounds costs $40; 4 1.OO0-pound steel
| powder enough to carry that projectile six
| miles at velocity of 2,600 feet second,
so that it would .o pierce tep inches of ar
..There are dozen or fifteen distinct and
| separate pieces in a Pinch gun. They are
| fitted one upon another by shrinking. AS
| the science Of gunmaking develops the ten
( dency Is toward smaller number of pieces
| and larger guns.
| what becomes of the old guns? Do you
| throw them away on the junk-heap?
Refining Old Guns.
| "By no means. BY spending 81 500 each
we can refine them: bore them out, fit In
new tubes and then rifle them, which will
make them as good as new When the
riling of a gun wears out it does not make
it dangerous 1t does not weaken 1t. but
| only destroys is accuracy"
| How many Pinch guns have we?"
about 300 scattered along both coasts"
| Where is the most powerful gun in the
/ world?"
The Most Powerful Gun.
| Down at Sandy Hook, waiting to be
! mounted. It is 46 feet long. 16-inch bore
| and weighs 100 tones. Heretofore the larg-
| and weighs 100 TONS Heretofore the larg-
| inch caliber, weighing about 1T tons each,
l have been mounted for several years to guard
| the approach to Spezzia. a naval station
south of Genoa. But ours is larger, and fires
| a heavier projectile with higher velocity
| With a charge of $40 pounds of powder It
| can carry projectile weighing 200
pounds at velocity-cf- $500 feet second
/ a distance of nine miles. as far as man can
/ see an object to shoot at This gun has
| been successfully built and tested. and
/ there is no reason why guns of 16-inch cali
Der should not be adopted for our coast