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. A major drawback of using the 6.8 Cartridge in an M4 style weapon has been the lack of reliable magazines. To solve this issue, we designed our SIX8 family of weapons around the magazine. Through a partnership with Magpul, the leader in polymer magazine engineering, we designed the first polymer 6.8 magazine. The SIX8 PMAG features many of the same design characteristics of the standard PMAG, including the curved shape and familiar texture. The body is slightly wider, and the walls were strengthened in critical areas. Our red follower makes the SIX8 magazine easy to pick out of a pile. The upper and lower receivers are designed to accommodate the slightly larger polymer magazine and to perfect the feed geometry for the 6.8 cartridge. As with the IC family, the weapons in the SIX8 family are fully ambidextrous. Our SIX8 rifles are, put simply, the familiar Stoner M4/AR-15/M16 architecture fully optimized for the 6.8 cartridge.