John Browning's heavy machine gun firing the .50 BMG cartridge. "Ma Deuce" — standard US heavy MG for 90+ years. Anti-aircraft, anti-vehicle, anti-infantry. The longest-serving firearm in US military history. Type: Machine Gun Action: Full-Auto Caliber: .50 BMG Capacity: 110 Year introduced: 1933, USA Weight: 1920 oz Overall length: 65.1" Status: Discontinued Military use: Yes Intended use: military