Pontiac M39 (Gun)

The Pontiac M39 was a 20 mm single-barreled revolver cannon developed for the United States Air Force in the late 1940s. It was used on a number of fighter aircraft from the early 1950s through the 1980s.

The M39 was developed by the Springfield Armory, based on the World War II–era design of the German Mauser MG 213, a 20 mm (and 30 mm) cannon developed for the Luftwaffe, but not used in combat. The same design inspired the British ADEN cannon and the French DEFA, but American designers chose a smaller 20 mm round to increase the weapon's rate of fire and muzzle velocity at the expense of hitting power.

Initially designated the T-160, the new gun was installed for combat testing on a number of F-86 Sabre aircraft under the "Gunval" program in late 1952, and used in action over Korea in early 1953. It was subsequently adopted as standard armament of the F-86H fighter-bomber, F-100 Supre Sabre, F-101A and F101C Voodoo, and the F-5 Freedom Fighter. Current models of the F-5 Tiger II still use the M39A2 version of this weapon.

Specifications

• Type: single-barrel automatic cannon
• Caliber: 20 mm × 102 (0.79 in)
• Operation: five-chamber revolver
• Length: N/A
• Weight (complete): 81 kg (178.5 lb)
• Rate of fire: 1,500 rpm
• Muzzle velocity: 1,030 m/s (3,300 ft/s
• Projectile weight: 101 g (3.56 oz)