The Democratic banner. (Mt. Vernon, Ohio) 1898-192?, 1915-10-19
TESTING A SHELL.
OrdeaIs Through Which a Big Gun
Missile Must Pass.
THE SOFT NOSE PRoJEcTlLE.

W. SSHS ~ 1vV0 tss wy sWVuSV
Heavy Armor Plate Without Explod.
ing Until After It's Impact Was Dis.
covered by Accident.
Everybody knows that the modern
shell is one Of the most diabolical of
mans inventions, but how many Of us
realize that 1t IL also one Of the most
delicate and complicated7
Recently some firms holding con.
tracts for making high explosive shells
took upon themselves to correct"
detail in the specification, and, as re-
suit, certain thread was improved"
They will never do anything Of the
kind again, because all their work was
rejected. The apparent absurdity-it
Is, in fact, an absolute absurdity. from
an engineering point Of view-is de-
signed OF set purpose.
There Is q somewhat similar an0m-
ally in the big shell for penetrating
armor plating. which was introduced
in consequence Of an accident. One
day test shell was fred at a piece Of
armor plating from the soft side. and
the projectile went clean through II
and exploded after impact. whereas .
similar shell fred against the 'front.'
the hardened and tempered side-shat-
tered and left an indentation Of only a
few inches.
This singular incident set somebody
thinking, and in consequence the high
explosive arm0r piercing shell Is now
given soft nose. To the hard point Is
attached cap of soft metal, with
which addition 1t will go through the
toughest piece Of armor plate. What
happens on impact seems to be this:
The cap spreads, holding the point and
SO enabling it-remember that the shell
is revolving rapidly-tO force its way
unbroken through the hard face Of the
plate by sort Of boring action.
No less curious Is another fact con-
cerning the points of such projectiles.
shells are left for weeks before they
undergo the next stage. because, strong
as they look, they are liable to snap.
Why? Think OF the razor. Constant
stropping twists the grain. with the re.
suit that the steel gets tired and will
not yield keen edge. But If you put
the thing away for few weeks the
grain will return to its normal state
and you can get satisfactory shave
In similar way the grain Of the steel
Is affected by working. though Of course
to much greater extent, and until 1t IL
''set" the makers must 60 cautiously
| Steel shows like, eccentricity In the
making of test gauges. Some of the
measurements of shells are very fine
and the instruments employed are Sc
delicate that they have to be used
quickly lest the heat Of the hand causes
the metal to expand.
Now. when a groove is cut In a piece
of steel which is TO be used as tes
gauge the work is laid aside for weeks
perhaps months. Why not finish it n
once? Because the groove. though dea,
true when cut out, may be otherwise IL
short time. even though 1t has beer
absolutely untouched.
As a concrete proof Of the elaborat
nature of projectile making take tn
case Of the shrapnel shell. The stee
portion undergoes about score of or
erati0ns, and the brass cartridge cas-
attached to the base requires about siS
teen, counting from the disk Of shee
brass to the finished article. The
there Ia the fuse. the delicacy of whic
resembles matchmaking.
Altogether the shell Is subjected (
about forty inspections and may be n
Jected at any stage.
After shell has survived this orde,
II ought to be, one would think. pc
feet. but test shell is taken fr0l
every l2O and actually fred from gu
into bank Of sand. 1t is then agai
, examined. and II the contour about Il
powder pocket IL expanded away gOt
the whole batch, because If they wei
fred the growing might be torn out I
the gun.
Perhaps the most striking illustrate
Of the minute care exercised In probe
tile making Is that every shell is weig
ed over and over again. II you produ'
an eighteen FOUNDER high explosi'
shell 1t must be only few drains ov
, or under Its normal weight; otherwl
, It is rejected.
| In this connection 1t may be Of inte
!. est to note that an explosive shell tn
, weighs only about seventy pounds W
!" break into a shower of some l.2
pieces. A single one Of the monst
projectiles fired from fifteen inch n
val gun will weigh 1850 pounds.
takes twelve seconds for the project
Of twelve inch naval gun to reach
. point Of impact when firing at ran
of five miles To fire battlesh
Q broadside costs about $4,000. = 4
r change.