CMMG Resolute 100 Upper Group MK4 5.56x45mm
The CMMG Resolute 100 Upper Group for the MK4 platform in 5.56x45mm is purpose-built for shooters who demand reliability and performance without compromise. Engineered as a complete upper group, it ships with the bolt carrier group (BCG) included, making it a ready-to-install solution for your MK4 lower receiver. The 16.1-inch barrel is crafted from 4140 Chrome Moly steel with a Salt Bath Nitride (SBN) finish, delivering outstanding corrosion resistance and long-term durability with a fast 1:7 twist rate optimized for stabilizing modern 5.56x45mm projectiles. The CMMG RML15 M-Lok handguard provides a slim, ergonomic profile along with ample attachment points for accessories, while the hard coat anodized finish on both the forged 7075-T6 aluminum receiver and handguard ensures lasting protection in the field or at the range. The Resolute 100 is the ideal foundation for a capable, no-nonsense AR-15-pattern rifle.
Product Highlights
- Complete Upper Group with BCG Included: Ships ready to pair directly with a compatible lower receiver, saving time and ensuring proven compatibility.
- 16.1" 4140 Chrome Moly Barrel with Salt Bath Nitride Finish: Provides exceptional durability, corrosion resistance, and consistent accuracy with a 1:7 twist rate.
- CMMG RML15 M-Lok Handguard: A free-float M-Lok design that reduces overall weight while offering versatile and modular accessory mounting options.
- Forged 7075-T6 Aluminum Receiver with Hard Coat Anodize: Delivers maximum structural strength and wear resistance for demanding use in any condition.
- Mid-Length Gas System and A2 Compensator: Promotes smooth, reliable cycling and features a standard 1/2-28 threaded muzzle for aftermarket device upgrades.
Specifications
- Brand: CMMG
- MPN: CMM55BC761
- UPC: 816422026562
- Caliber: 5.56x45mm
- Barrel Length: 16.1"
- Barrel Twist: 1:7
- Barrel Profile: Medium Taper
- Barrel Material: 4140 Chrome Moly (4140CM)
- Barrel Finish: Salt Bath Nitride (SBN)
- Muzzle Device: A2 Comp, threaded 1/2-28
- Gas Port Location: Mid Length
- Receiver: Forged 7075-T6 Aluminum, M4 Type Upper, Complete with BCG
- Handguard: CMMG RML15 M-Lok
- Finish: Hard Coat Anodized (Receiver and Handguard)
- Charging Handle: CMMG Mil-Spec
- Weight: 4 lbs 5 oz
- Overall Length: 25.2"
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