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.” From the LWRC (Land Warfare Resources Corporation) website, it is stated that the 6.8X43MM SPC II cartridge was developed as a part of the Enhanced Rifle Cartridge Program to address the deficiencies in terminal performance seen with 5.56x45mm NATO cartridge while allowing the soldier to carry the same number of rounds with a minimal weight penalty. By using a heavier projectile, the 6.8 round offers more impact energy than the 5.56 NATO round across all effective ranges, effectively bridging the gap in lethality between 5.56 NATO and 7.62 NATO