Perrysburg journal. (Perrysburg, Wood Co., O. [Ohio]) 186?-1965, 1898-10-08
UNCLE sAM,s BIG GUNS.
How the Huge FOrgIngs Arc Assem-.
bIed In the Government Gun
Foundry MT Washington.

In st. Nicholas there Is an illustrated
article on THE Gun Foundry at Wash
ington." The author says: The guns
are made of what is called forged
steel. This steel is made by private
firms, principally at the famous Beth
,ehem works in Pennsylvania, and is
sent to the gun foundry in the shape of
large tubes, and in other shapes called
jackets and hoops. These steel pieces,
after being finished, are put together
and mad into guns. The jacket of a
gun is about half the length of the
tube, and itself is really a large tube.
The inner tube, when it arrives, is put
into lathe, and has the hole bored out
to nearly the size it will be when fin
ished; then it is turned down inside for
about half its length from the rear or
breech end to its proper size. Turned
down" means that the metal is cut off
with a steel cutter. The jacket also is
bored out smoothly and the hole care
fully measured. The diameter of this,
hole, or bore, in the jacket is little
smaller (some hundredths of an inch)
than the outside of the tube after be-,
ing turned down.
Overhead in the shop are big cranes,
which travel back and forth on tracks,
and which can easily lift and carry,
heavy weights. The largest crane is
called the 110-ton crane, but it will lift,
Il weight even greater. Near the center,
of the gun shop is large pit in which
there are furnaces. After the tube,
has been bored out and turned down
outside, it is carried by crane and
lowered into the pit near the fur
naces, so that it stands on it's muzzle!
end. the breech end being up in the air,
The jacket is also lifted and lowered.
into a furnace and heated. This fur.
mace has top, or cover, which lifts,
off, and which is put on after the jacket
has been lowered into it. Hot air is
forced into this furnace, which heats
the jacket till it expands so that the
size of its bore becomes greater in
diameter than the size of the tube it is
to inclose. When all is ready, the
cover is lifted from the furnace, the
crane hooks on to the jacket, lifts it
out of the furnace, and swings it over
the tube. The jacket is then quickly
measured, and carefully lowered over
the tube, which is standing on its end.
A stream of cold water is then ad-
mitted into the lower end of the tube.
This water rises nearly to the top of
the tube, and helps to cool both tube
and jacket, now fitted together. AS
the jacket cools it shrinks to its proper
size, and so squeezes and holds the tube
tight within.
When both are cold, the partly made
gun is lifted out of the pit, put into an
other lathe, and turned down outside
so as to be ready to have the hoops
put on. These hoops, which have been
bored out to the proper size, are heated
and shrunk on over the gun just as the
jacket was shrunk on over the tube.
The whole gun is made, or built up in
this manner. After all the hoops are
on, the gun is bored out again to final
size, put into rifing machine, and
rifled; that is, it has grooves cut in
side of the bore throughout its length.
These grooves commence at the muz-
Zle, and gradually curve till they reach
the end of the bore. They are cut by
what is called rifiing bar, which is a