The sun. [volume] (New York [N.Y.]) 1833-1916, 1892-01-14

Ceasinsaeasa sfthe Tests ~ the Inaian Head
PROVING 0rouuA.

AMOR PLATE 1RLAIa
Coassnustssa sfthe Tests ~ che IAafsn Head
rroviae 0roura.
WASHINGTON. Jan. lathe Beard OF naval
of1csrs which recently conducted the armor
plate trials at Indian Head proving ground.
was called upon to-day to complete the tests
by firing upon two plates from the Carnegie
works. one. An ail-steel plate Of low carbon.
and the other high carbon nick steel plato
Of high carbon. both treated BY the Harvey
process.
As on previous nringe. a six.inch and an
eight-inch gun were used. the former dis
charging Holtzer and the latter Carpenter
projectiles. Brown prsmatio powder from the
Dupont works was used. As in the tests OF
October and November. when similar plates
we're fired Mt. the striking velocity In the six
inch gun was 2.O75 foot seconds. and the
striking energy was 2.9S9 foot. tons.
In the S.inch gun the velocity was 1850 foot,
seconds. and the energy 1880 foot. tons. 1t
was intended to FIRE Ave shots at each plate.
the last round being from the S-inch weapon.
but the programme was changed on account
Of an inequality In the nickel plate which had
been shortened 10 inches. Only four shots
were fired at this plate. three Of them with
8-inch projectile.
perfect comparison Of the all.steel plate
with Its companion. or with the plates attacked
in November. is made difficult by the fact that
It had been blamed and was not OF uniform
thickness. and that the experiments during it's
process OF manufacture had included its tenn
pering eleven times. which must have some
what altered it's nature. Both plates. there
fore. we're to certain extent crippled. and In
the case OF the nickel plate the modification OF
the condition made was not sufficient
to overcome It's disability. It was severe
test for any plate to FIRE four shots at its CEN
tire. The results. however. sustain the conclu-
sions drawn form previous trials. and while
the nickel high carbon plate was torn apart 1t
held out against attack until the final round.
The following are the balistic details By
rounds:
ROUND oSE-First shot against the high car
bon nickel plate. the proiectile penetrated into
the packing probably. for the base OF the shell
was two inches from the surface OF tho target
The shell remained in the aperture OF It's max
ing. There we're no cracks or damage other
than local. such as 81 ght radical cracks in the
fringe at the point Of Impact.
bon all steel plate. The point Of the shell en-
tered the plate Inches and sha
later in tho day other slivers detached them.
selves. The indent was clean cut, tho edges
Rogsn fhe
carbon plate. The penetration was ten inches.
the shell p
connecting the, second point Of impact with
VI" ROUND e Foun Second shot against the low
carbon plate. The projectile penetrated 1889
sase ens
ments. which flew in all directions and at At
great distances. There were g. lew RACIAL 1t1s.
HOUND F1vE-Third shot against the low
the target until seventeen. INCHES remained be-
tween projectile base and the surface OF the
sas sef TIM
we're were also tho short radai cracks and fringe
about RoHs she sPsThrd shot against the high
carbon plate. The rrojeetile entered eleven st;e,
nas wtR good pePon su
from fo TIE point Il impact 70 the LETT Side. As
'g Ronsb bssss shot against the low
carbon plate, The penetration was 22.: inches y
h"a psse ss
ths t p9ns Of .h %Rhs to the Meafnsss
e Her ehs ,sssss n.sSraly e s.Psstsd !sS@
half a greater power OF resistance. The other
cracks deepened. The shell remained in the
plate.
enable tho discharge OF the eiEht-inch pro-
jectiles was accomplished in a little over an
hour.
carbon plate. The projectile perforated the
steel and was picked up behind the earthworkss
Connecting the first, NTH. and fourth points OF
impact and continuing downward to the hot !;
and deerened. The oak backing was badly
HOUND N1SE-Fourth shot at the high car
bon plnte All interest centred on the effects
Of this shot. The shell went completely
through the plate. tearing the plate asnnder
transit The little crack OF a previous round
becams gaming daa assure Irscss and dns other
tending from the middle of the top
through the first to the eight-inch point OF I'm
pact, another from tho latter through the Sec
ond point to the left edge. and third from t.
right hand bottom corner. dividing the plate
into three triangular portions and completely
damolishine 1t as far as its services as an armor
plate was concerned.