The XM312 is a heavy machine gun derived from the XM307 25 mm autocannon and chambered for the .50 BMG cartridge.
Weight: 40 pounds (20 kg) max. (weapon only).
40 pounds (20 kg) max. (ground mount system).
Dimensions: 9.9W × 7.2H × 61.5L max. inches (251 mm × 183 mm × 1562 mm) (52.5L, 1334 mm) charged).
Portability: Man portable or vehicle mountable.
Stability: Up to 18 inch (460 mm) tripod height.
Operation: Currently a hybrid gas & recoil operating group. Gas powers the bolt mechanism while recoil drives the barrel/barrel extension and the feed system. Design changes are underway to totally eliminate the gas system to provide increased reliability and reduced complexity.
Environmental: Operationally insensitive to conditions.
Reliability: 6,000 MRBF (threshold) / 10,000 MRBF (objective).
Rate of fire: 260 rounds per minute (4.3 Hz)(cyclic).
40 rounds per minute (0.7 Hz) (sustained, without barrel change). In burst of five to seven rounds, the same as the M2HB.
