Ammunition for 3.2-inch Gun.
The ordinary friction-primer is used for radial vents; for axial vents an attachment is made to the friction-primer of a thin brass wire about 18 inches long, looped or coiled for convenience, and having one end fastened in the loop of the friction-wire, and the other around the head of the body of the friction-primer.
The cartridge-bag is used, but experiments are now being made with metallic cases. (This proposed metallic ammunition for 3.2-inch guns comprises a projectile weighing 16½ pounds, with a suitable charge of smokeless powder to give an initial velocity of 1450 ft.-sec.)
| Charge of powder | 3¾ pounds I. K. |
| 3½ " sphero-hex. | |
| Weight of projectile filled | 13½ " |
| Bursting-charge of shell | 7 ounces |
| Bursting-charge of shrapnel | 3 " |
Shell, shrapnel, and canister are used.
Shell.—The base-percussion-fuze shell ([Fig. 42]) is made of cast iron in one piece, having a band of soft brass or copper forced into a recess on the outside, ⅝ of an inch from the base. The body and half of the head are painted black; the half of the head nearest the point is painted vermilion.
Canister.—The canister ([Fig. 43]) consists of a hollow cylinder of malleable iron, with one end closed by a cast head. The case is filled with from 222 to 226 balls, and a metal cover is inserted. Around the case are several slits, their ends overlapping to secure the thorough breaking up of the case on discharge.
Fig. 42.
Fig. 43.
There are several small holes in the head, through which a portion of the gas of the exploded powder-charge enters, drives forward the balls, and assists in disrupting the case.
Total weight of a round, 11 lbs. 10 oz.
This projectile is painted black.
Fig. 44.
Shrapnel.—The Frankford Arsenal shrapnel ([Fig. 44]) weighs 1310/16 lbs. Exclusive of filling it consists of three parts, viz., head (d), body (a), and base (b). The head is made of cast iron, bored and threaded to receive the fuze, and contains a powder-chamber which is lacquered to prevent danger of premature ignition by friction. The body is made of lap-welded wrought-iron or low-steel tubing, and is weakened for fracture by circular and longitudinal grooves on the inside. It contains 162 hardened lead balls, ½ inch in diameter, which are assembled in circular layers and held in position by cast-iron separators, which increase the effect of explosion by furnishing additional fragments. The base is made of cast iron threaded to screw into the cylindrical case, and is so formed as to provide a support for the copper band to prevent deformation of the case at this point from shock of discharge, c is the rotating band. This projectile is painted, body black, head vermilion.
| Total weight, ready for firing | 13 lbs. 10 oz. |
| Total number of balls and individual pieces | 201 |
| Bursting-charge | 3 ounces |
SHRAPNEL MADE BY AMERICAN PROJECTILE CO.
Fig. 45.
The entire case is of wrought steel electrically welded together so as to form a complete hardened wrought-steel case without joint. The powder-chamber is formed in the base by a hard wrought-steel diaphragm (d) supported by a cast-iron spider, and connected through the centre of the shell (axially) to the fuze-opening by a cast-iron tube. It is smooth-finished, and either tinned or lacquered. The shell contains 170 bullets (34 to the pound) packed in circular layers, and they are held firmly in position by a resin matrix. The bullets are introduced through a hole at c.
The exterior is painted as follows: body from the band forward, to include three fifths of head, black; remaining part of head, and part of body in rear of band, vermilion. The band is of copper.
| Total weight of projectile complete | 13½ pounds |
| Total number of balls and individual pieces | 228 |
| Weight of bursting-charge | 3 ounces |
The Frankford Arsenal combination fuze is used. This fuze weighs 17½ ounces; but if made of aluminum it will weigh only 7¾ oz. For field-artillery guns it is graduated from 1 to 15 seconds, the graduations being based upon the time of burning in flight. Each entire second is marked by a through-hole in the cone-cover, and each of these spaces is sub-divided into six equal spaces by holes nearly through the cover, which for the 3.2-inch gun will correspond to the following distances, viz.: 70 yards at 1000 yards range; 55 yards at 2000 yards range; 48 yards at 3000 yards range; 42 yards at 4000 yards range.
The following table gives the mean of five shots in each group:
| Seconds. | Range. |
| 2 | 883 yards |
| 3 | 1401 " |
| 5 | 1966 " |
| 6 | 2433 " |
| 8 | 3037 " |
| 9 | 3461 " |
| 12 | 4225 " |