6mm ARC

The 6mm Advanced Rifle Cartridge (6×38mm), or 6mm ARC for short, is a 6, (.243) caliber intermediate rifle cartridge introduced by Hornady in 2020, as a low-recoil, high-accuracy, designed for use in the AR 15 platform at request of a specialized group within the U.S. DOD for its multipurpose combat rifle program.