Alliant Techsystems Inc. (ATK), a subsidiary of Orbital ATK, has received an $100,2 million contract for the production of the M829A4 120mm Armor Piercing, Fin Stabilized, Discarding Sabot with Tracer cartridge, according to the U.S. Department of Defense.

The three-year contract funds the production of the M829A4 Advanced Kinetic Energy (AKE) rounds that are specifically modeled for the 120mm main gun on the Abrams M1A1 and M1A2 main battle tanks.

The A4 variant was under development by General Dynamics Ordnance & Tactical Systems and Alliant Techsystems (ATK until ATK received a $77-million, three-year contract on 11 July 2011 to develop and qualify the M829A4 Advanced Kinetic Energy (AKE) round for the US Army’s M1A2 SEP (System Enhancement Package) Abrams MBT.

The M829A4 is a fifth-generation APFSDS-T cartridge consisting of depleted-uranium penetrator with a three-petal composite sabot; the penetrator includes a low-drag fin with a tracer, and a windshield and tip assembly. Its propellant maintains consistent muzzle velocities across operational temperatures from −25 to 145 °F (−32 to 63 °C). The new Advanced Combustible Cartridge Case is similar to previous models but has a relocated skive joint placement for better crew-member safety during handling. The initial order for 2,501 M829A4 rounds in 2014 had a unit cost of $10,100 each.

On 20 July 2015, Orbital ATK announced that the M829E4 had passed First Article Acceptance Testing and was entering production. On 12 October 2015, Orbital ATK announced the round had recently received type classification as the M829A4, and was awarded a full-rate production contract to begin in early 2016.