Iowa County democrat. [volume] (Mineral Point, Wis.) 1877-1938, 1917-08-09
The BIGGEST Guns
Those Used on Land Outweigh the
Largest In the Navy.
OUR COAST DEFENSE GIANTS.

Hook and Panama Can Sink Vessel
Before 1t Appears Above the Horizon.
How the Big Guns Are Made.
There are two classes Of guns-navai
guns and army Or land guns. Because
they can be manipulated more easily
than those Of ship, land guns are the
heavier. The largest naval gun is the
fifteen inch gun, and the largest land
gun is the German hoWitzer, or 16.5
inch gun.
OF the two the naval gun fires shell
weighing over half a ton, while the
other fires projectile ton in weight.
But the new giant sixteen inch guns
of the United States defending the
Panama canal and New York at Sandy
Hook shoot projectiles weighing 1870
pounds, which is over a ton. These
immense steel guns can sink a ship be-
fore it has really come into sight Oh
the horizon, the location of the battle
ship having been determined by air
plane or tower.
How these huge pieces are made is
described as follows by the Popular
Science Monthly. The first step is the
making Of the pig iron from iron ore
in large furnaces like towers, called
blast furnaces. Then the pig iron is
melted with other steel in large steel
furnaces called 'open hearth" until it
is freed of it's impurities and convert
ed into steel.
The melted steel, thin as water, is
run from these furnaces into big iron
molds, where it is allowed to cool into
/ large solid cylindrical or corrugated
blocks After cooling these are reheat-
ed and reduced in size by pounding
thcu with big steel hammers and
squeezing them in rolls until at last
the steel is pressed into a long barrel
like mass, the embryo of real gun.
This long skeleton Of the inside Of
gun must be bored out from one end
to the other on immense lathes, some
over ninety feet long. Heavy as the
mass is, a huge lathe turns it around
as easily as body turns spool.
After the inside has been rif1ed Or
scored to form an inside surface that
gives the shell twist before it leaves
the muZZle and causes it to fly straight
the lower or muzzle end of the gun is
made larger This may be accomplish
ed in one or two ways. Either adN-
tional shorter steel tubes are placed
over the main inner tube, or the main
tube is wound with wire and finished
%,rl VIII, ~
guns are usually the heavier and are
used on board ship.
The gun bound with wire is really
stronger than the one built OF bands or
rings of steel, one on another, for the
wire re-enforces the gun tube so that
it will safely withstand the tremendous
strain which is constantly put on it
when it is fired, said to be as much as
seventeen tons pressure on each square
inch.
In the case of built up gun, as
it is called when made of hoops or
bands of steel, the outer tubes or rings
are shrunk or sweated on-that is, they
are heated so that they expand or swell
q little, as all steel does when heated,
and then while hot they are fitted over
the inner part and allowed to cool and
shrink, or contract. In so doing they
fit Very tightly on the main tube.
In making a wire wound gun the
wire is wound or coiled around ana
around until more than 100 miles of 1t
has been wrapped around the big can
nom A twelve inch gun requires III
miles Of wire, weighing about thirteen
and one-half tons Although the
strength of the wire is such that 1t
gives great resisting force to prcssures
exerted sideways, it does not lestoW
strength lengthwise Therefore an ex-
ira thickness of metal must be put on
the muzzle Of the gun, where the vi
bration caused by the shell leaving the
gun is the greatest.
The breech, or the back end of gun,
is a very important part. Here the
chamber. After the shell is in place
the breech is Closed by the shutting of
@ very complicated and strong door.
It is fastened or fitted in the gun by
extremely strong screws, so that the
charge will not burst the gun open at
the back when it is fired.
Sometimes a shell explodes in the
barrel of the gun. In a wire bound
gun the wire tends to prevent grave
disaster. It binders the steel tubes
from bursting into many pieces and
flying in every direction The solid
gun is wholly built of tubes, while i'll
the wire wound gun there may be one
or two tubes, over which the wire is
wound with the jacket tubes shrunk
over the wire. A bush for the breech
ring is screwed into the rear cid,
which is also REINFORCED by a breech