The CMMG Dissent Mk4 Upper in 22 ARC is a bufferless 16.1 assembly featuring a patent-pending Compact Action and direct impingement system. This design houses the entire recoil assembly within the upper receiver, eliminating the need for a traditional buffer tube. It features a 16.1 barrel with a 1:7 twist and includes an adjustable gas block. This complete group comes with a bolt carrier group, a ZEROED Muzzle Brake, and a left-side non-reciprocating charging handle. Optimized for 22-250 performance, it is compatible with any standard AR-15 lower receiver. Finish: Tungsten Grey