CMMG UPPR RSLT MK4 350LEG 16.1″ BLK

Description

The CMMG Resolute MK4 is a complete upper receiver built around the .350 Legend cartridge, making it a practical choice for deer hunters who want AR-15 ergonomics in jurisdictions that require straight-walled rifle cartridges. Paired with a compatible mil-spec lower, it converts an existing platform into a capable hunting rig without requiring a dedicated build from the ground up.

The 4140 Chrome Moly barrel carries a salt bath nitride finish, which provides corrosion resistance and surface hardness without the added weight of a heavy-profile tube. The medium-taper contour keeps the upper manageable in the field. A 1:16 twist rate is deliberate here: .350 Legend is loaded with relatively light, large-diameter bullets compared to centerfire rifle cartridges, and a faster twist would over-stabilize them, degrading accuracy. The 1:16 rate is matched to the typical bullet weights this cartridge actually runs.

The carbine-length direct impingement gas system keeps the reciprocating mass moving at a rate well-suited to the .350 Legend’s pressure curve, and the CMMG ZEROED muzzle brake on a 1/2×28 thread reduces felt recoil further, which matters when you need a steady second shot in hunting conditions. The billet 6061-T6 aluminum upper receiver wears a Cerakote Armor Black finish, and the CMMG EML15 M-LOK handguard gives you a free-float rail for consistent barrel harmonics and attachment points for lights or a bipod. The ZEROED ambidextrous charging handle and a polymer dust cover are included, as is a bolt carrier group, so this upper is ready to mount without sourcing additional components.