The US Army Armament Research, Development and Engineering Center (ARDEC) is developing a new kind of .50 caliber ammunition called the All Purpose Tactical Cartridge, according to a presentation given at this years National Defense Industry Association small arms conference. The new round will be a sabot design, similar to the existing .50 cal M903 SLAP round, but apparently with a more streamlined shape and better accuracy.
Recently, Senators as part of the Senate Armed Services Committee questioned Army Chief of Staff General Mark Milley about the need to penetrate advanced body armors which are now coming to market in increasingly large numbers. A smaller caliber round similar to the All-Purpose Tactical Cartridge which fires a hardened projectile at very high velocity using a sabot to improve efficiency could be just what is needed to fill this role, and potentially could do so without the use of expensive tungsten material. While the APTC is much larger than would be necessary, proving the technology with a .50 caliber round could be the first step towards its application in a smaller caliber round. Notably, the project plans to combine the sabot projectile design with lightweight composite cases, already troop-tested via the Mk. 323 Mod 0, which should result in very lightweight ammunition relative to other .50 caliber rounds. Potentially, this could allow the new APTC to function as a powerful anti-armor force multiplier for light vehicles, if coupled with a lightweight .50 caliber machine gun. The round is also said to incorporate One-Way Luminescent (OWL) tracer technology.
The new round is slated to complete engineering and manufacturing development, the last step before fielding, by the 1st quarter of 2023.