CMMG Resolute Mk4 300 Blackout 14.5" Coyote Tan

The CMMG Resolute Mk4: Compact Power in 300 Blackout

The Resolute Mk4 represents a thoughtful solution to a genuine problem: the need for a rifle that delivers real ballistic performance without the bulk of a full-size carbine or the legal complications of a short-barreled rifle.

Design and Specifications

Built on the proven AR15 platform, this rifle chambers the .300 Blackout cartridge—a round originally designed to maximize the effectiveness of suppressed fire while maintaining compatibility with standard AR15 components. The 14.5" barrel is pinned and welded with CMMG's ZEROED SVD brake, bringing the overall length to 16.1", keeping the rifle compact without requiring SBR registration.

Features and Ergonomics

Handguard and Mounting:

• EML 15 handguard with M-LOK attachment slots at 3, 6, 9, and 12 o'clock positions
• Full-length M-LOK coverage on both sides and bottom for maximum accessory mounting flexibility
• Reduced weight compared to full-length Picatinny designs

ZEROED Parts Suite:

• Ambidextrous safety lever with 60/90-degree positions
• Ambidextrous magazine catch and extended mag release button
• Drop-in trigger for crisp, predictable breaks
• Ambidextrous charging handle for left and right-handed shooters
• Polymer dust cover and AR15-pattern bolt catch

Included Accessories:

• Magpul 30-round PMAG magazine
• RIPSTOCK sling attachment system

Performance and Versatility

The .300 Blackout excels with both subsonic and supersonic loadings. Subsonic ammunition makes this rifle ideal for suppressed use and close-quarters work, while supersonic loads extend effective range significantly. This versatility means a single rifle can serve home defense, tactical training, and field use.

When full-size rifles prove too cumbersome and pistols or short-barreled rifles don't deliver the ballistic performance you need, the Resolute Mk4 fills the gap with style and substance.