Description
The M829A2 cartridge is a kinetic energy, armor-piercing, fin-stabilized, discarding sabot, fixed round with tracer (APFSDS-T). This antitank round is intended for use in the M256 smooth bore gun and is designed to provide terminal effectiveness over the M829A1 cartridge.
The M829A2 is a U.S. design developed 120mm APFSDS-T cartridge. The complete round contains a propulsion/ignition system and an inert projectile which is similar to the M829A1. The propulsion/ignition system consists of a combustible cartridge case with a metal cartridge case base, granular and stick propellant, and an M129 electric primer. The subprojectile assembly consists of a depleted uranium penetrator, with windshield and windshield tip fitted to the front, and a six-bladed aluminum fin and tracer assembly fitted to the rear. The projectile consists of the subprojectile combined with a sabot, an obturator and a silicone seal. The sabot is composed of three 120 degree noninterchangeable segments with internal grooves matching those on the outer surface of the penetrator. The sabot has a silicone rubber seal at the rear to prevent leakage of propellant gases. A nylon obturator is used to prevent propellant gases from leaking around the outside of the sabot.
The projectile is black with white markings.
Functioning
The M829A2 is loaded and fired from the M256, 120mm in the normal manner. Initiation of the electric primer ignites the propelling charge and combustible case, generating gases which drive the projectile from the gun and ignite the tracer. The silicone seal at the rear of the sabot prevents gas leakage between the sabot segments and the driving forces (gas) propelling the subprojectile downbore. Upon leaving the gun, aerodynamic forces cause the sabot to separate from the subprojectile allowing the subprojectile to continue on a true course to target while the sabot segments fall quickly to earth. Target penetration is effected strictly by the high kinetic energy of the subprojectile impacting the target.
Hazardous Components
Primer - M129
Physical Data
Length, overall - 38.75 in, 984.3 mm
Length, projectile - 30.79 in, 782.1 mm
Length, penetrator - 30.79 in, 782.1 mm
Diameter, penetrator - 0.84 in, 21.3 mm
See Also
Cartridge, 120mm APFSDS-T, M829A1
Source(s)
