Cartridge, 90 mm: APC-T M82

contains an Explosive D charge weighing 140 g. The base of the cavity is enclosed by a threaded assembly consisting of a BD M68 or M68A1 fuze with a delay function and an integral red tracer which burns for a minimum of 3 seconds after firing. On impact with a target the steel windshield crumples allowing the armour-piercing cap to penetrate the target armour by kinetic energy, protecting the hardened tip of the main projectile in the process. The projectile can then enter the target interior before the high-explosive charge detonates inside. The 70:30 brass cartridge case is of the M19 type with an M28A1 or M49 percussion primer press fitted into the base. The propelling charge can vary between 3.316 and 3.656 kg of M6 propellant, depending on the required muzzle velocity. An igniter pad may be located beneath the projectile to ensure uniform ignition, although this is not always fitted. The muzzle velocity of the 90 mm APC-T M82 may vary between 790 and 851 m/s. Maximum range is 19,570 m. The 90 mm APC-T M82 can penetrate 130 mm of face-hardened armour at 450 m. The 90 mm APC-T M82 replaced the earlier 90 mm AP M77. It was one of the rounds developed during the Second World War for the 90 mm anti-aircraft gun M1, the 90 mm T13 anti-tank gun series and the 90 mm T7/M3 series of guns used in M26 Pershing MBTs. When the M26 MBTs were phased out of service in favour of the M47 and M48 MBTs, the 90 mm APC-T M82 remained in service. It is, however, no longer deployed by the US armed forces as gun-armed M47/M48 MBTs have been removed from US service.