Chambers: 5.56 NATO/223 Rem., 223 Wylde, 6 ARC, 300 BLK. 5.56 barrel: 16”, 1:7” twist, or 16” 1:8” 223 Wylde Hanson-profile stainless steel. 6 ARC 18” 1:7.5” twist Proof Research full profile. Thermal-fit barrel, precision billet upper with flat barrel seat, ArmorLube BCG. Proprietary buffer system with flat wire technology. Lower receiver has right-side bolt release, flared mag well, E Series Cerakote finish. SEE POLITICAL PANIC PRICING.