Connecticut western news., 1883-07-18
MAKING STEEL CANNON.
How Great Guns are Manufactured at the
 Washington Navy Yard.

The Washington Republican says: The two new six inch steel guns now be- ing constructed in the ordnance shops at the navy yard will probably not be fin ished for several months. The work of building them is necessarily 8 slow one. All the labor is performed in the shops here, except the manufacturing of the steel. That is done at the Midvale Works. in Easton, Pa. The steel then is shipped to Washington, and the work of converting it into cannon is performed. This is complex operation, and to the locker on is decidedly interesting. The steel is first turned by lathe working slowly, but with tremendous power un- til the heavy mass of ''steel in the rough" so to speak, becomes long cylindrico- conoidal column. In this condition it is placed in proper position and hole drilled clear through it by means of what is called 'hog bit. " This hog bit is 8 small rectangle of very hard steel, turned up at one end in such @ manner as to form rude vertical sec- tion of spherical triangle. The whole rectangular piece is then clamped down upon fiat shaft of chilled iron in such a manner as to fit in and form one piece with the shaft. The latter has at the opposite end cylindrical shape, which end is held in 8 frame and worked by appropriate machinery moved by steam upon one end of the steel column to be perforated. The end of the column is first ''dug into'' little, and then the ''hog bit'' does it's work. It revolyes on i its axis and the bit" describes rfrcie, tearing out the hard steel slowly but surely. As the guns have bore of six inch diameter, and the bit describes a circle of only two and three-quarter inches radius, the enlargement of the perforation is accomplished by other bits.
 Once perforated the now hollow tube of steel requires to be "jacketed," !" 'col Jared" and 'breeched" before it is al lowed to graduate into the society o cannon. The jacket is an outside wral of steel, hollowed in the same way heated until it expands sufficient to bt slipped over the tube it is intended tt jacket. Upon cooling this outside wral contracts and presses upon the now in side tube with almost the same degre' of cohesion as the molecules of the stee
 themselves. The object of the 'jacket' is to strengthen the gun and proven
 accident The explosive force of gase
 evolved from gunpowder being tremen
 dous and occurring mostly at the breecl
 the primary object is to strengthen thi
 latter part. Collars of steel, great block of carbonized iron having been turne into shape and perforated, are next ez banded by the hsat and slipped over tn l breech part of the gun. When con , tracting they grow into and become part of it. The breech head of the gu
 is next lathed and fashioned, differer , workmen being employed on differe1 parts of this. The rifiing of the gun
 another step. A different kind of "bit , from the "hog," spur of steel tempere 3 to great hardness, is clamped to the Gel f Ire of semi-circular piece of copp' D and iron, and this last device is slow : worked through the gun on a spiral tur
 giving the ''rife twist" The breed head is then grooved and adjusted al e the breech cap formally adjusted. Thi
 as is known to all who have examine J. breech-loaders, swings back on hing 0 or spring, and when closed is secure V locked by lever clamp.