The CMMG Banshee Mk3 Upper in 8.6 Blackout is a high-performance 16.1 assembly built on the AR-10/LR-308 (DPMS Gen 1 High-Pattern) platform. It features a 4140 Chrome Moly steel barrel with an ultra-fast 1:3 twist rate, specifically engineered to stabilize heavy projectiles for the 8.6 BLK cartridge. The Armor Black Cerakote receiver is equipped with a direct impingement operating system and an adjustable gas block for fine-tuning suppressed or unsuppressed fire. Designed for any standard Mk3 or SR-25 pattern lower, this upper delivers massive subsonic energy and long-range supersonic capability. Note: This Mk3 series upper requires an AR-10/LR-308 style bolt carrier group and lower receiver.