6.8mm REMINGTON SPC

The following from the Wilson Combat website: “The 6.8 Special Purpose Cartridge (6.8x43mm) was initially developed by MSG Steve Holland and Chris Murray, a United States Army Marksmanship Unit gunsmith to offer superior downrange lethality over the 5.56 NATO/.223 Remington in an AR pattern service rifle with minimal loss of magazine capacity and a negligible increase in recoil.”