M1 40mm Gun, emplaced with outriggers. (TM 9-252, May 1952)

M1 40mm Gun, rigged for traveling. (TM 9-252, May 1952)

M1 40mm Gun

Every gun section possessed one truck-drawn 40mm gun. Based on a design by Bofors, a Swedish firm, the gun itself was also used extensively by the US Navy, in twin and quadruple mounts, aboard just about every type of vessel, from battleships to transports.

Caliber: 40mm (1.57 inches)

Muzzle Velocity: 2,870 feet per second

Range, Horizontal, with Armor-Piercing Shot: 9,475 yards

Range, Horizontal, with High Explosive Tracer: 5,200 yards (to tracer burnout)

Range, Vertical, with High-Explosive Tracer:5,100 yards (to tracer burnout)

Type of Fire: Single or Automatic

Maximum Rate of Fire: 120 rounds per minute

Capacity of auto loader: 7 rounds (manually loaded); 8 rounds (in clips)

Weight of complete weapon with computing sight: approx. 5,900 pounds

Wheelbase: 10 feet, 6 inches

Length (rigged for travel): 18 feet, 9.5 inches

Width (rigged for travel): 6 feet

Height, in battery, at maximum elevation: 13 feet, 9 inches

Maximum elevation, manual: 90 degrees

Maximum depression, manual: -6 degrees (on carriage)

Maximum depression, manual: -11 degrees (with jacks on level ground)

Traverse: 360 degrees

Emplacement: Maximum slope on which weapon may be leveled: 5 degrees

Data from TM 9-252, 40-mm Automatic Gun M1, 40-mm Antiaircraft Gun Carriage M2A1, and 40-mm Gun Mount M3, May 1952.