CMMG Resolute MK4 .338 ARC 16.1in 10rd Armor Black

About this product

The CMMG Resolute MK4 .338 ARC 16.1in 10rd Armor Black is a semi-automatic rifle that bridges the gap between traditional AR-15 platforms and large-bore hunting capabilities, featuring full parts compatibility with standard AR-15 components where possible and chambered in the formidable .338 ARC cartridge. Built by CMMG with their proprietary ZEROED components system, this rifle ships ready for optics mounting and suppressor use with its threaded 16.1-inch barrel, while maintaining a compact 35.5-inch overall length that balances maneuverability with ballistic performance. The adjustable RipStock and slim EML 15 handguard round out a package designed for hunters and shooters who need extended range and terminal energy without stepping into heavier bolt-action systems.

What is the CMMG Resolute MK4 .338 ARC used for?

This rifle is built for medium to large game hunting and long-range shooting where .338 ARC's ballistics outperform traditional .308 Win or 6.5 Creedmoor rounds, delivering over 2,800 ft-lbs of energy at the muzzle with appropriate loads. With its 16.1-inch barrel and semi-auto operation, it offers faster follow-up shots than bolt-actions like the Stevens 334 in .308 Win, though it sacrifices some velocity compared to longer-barreled alternatives. The M-LOK handguard and threaded muzzle make it suppressor-ready for hunters prioritizing reduced noise signature in the field.

How does the CMMG Resolute MK4 compare to the Stevens 334 in .308 Win?

The Resolute MK4 delivers significantly more energy and flatter trajectory than the Stevens 334 .308 Win, with .338 ARC generating 450-500 more ft-lbs at 300 yards while maintaining semi-auto functionality. Where the Stevens 334 is a 7.1-pound bolt-action rifle with a 20-inch barrel, the CMMG offers faster cycling and modular AR ergonomics at 6.2 pounds, but requires stricter attention to NFA regulations if configured with a stock under 16 inches. For hunters needing rapid target re-engagement or custom accessory setups, the CMMG is superior; for pure precision bench shooting, the Stevens’ locked bolt may offer slight consistency advantages.

What does it weigh and what are the dimensions?

Unloaded weight is 6.2 pounds (2,812 grams), with an overall length of 35.5 inches and a 16.1-inch cold hammer-forged barrel featuring a 5/8x24 thread pattern. The RipStock adjusts over 1.5 inches of length of pull, accommodating shooters from 5'8" to over 6'4", while the handguard provides 13.5 inches of continuous M-LOK real estate for lights, bipods, or forward grips. These dimensions make it nearly 4 inches shorter than most 20-inch barreled rifles while maintaining legal non-NFA status.

Who is this NOT for?

This rifle isn’t for beginners or budget-conscious shooters, as .338 ARC ammunition costs roughly $2.50 per round compared to $0.80 for .223 Remington, and the platform demands understanding of gas system tuning for reliable cycling. It’s also poorly suited for high-volume range days due to barrel heat dissipation limits—after 40 rounds in 10 minutes, groups will open up significantly until cooled. Lastly, those in states with magazine capacity restrictions should note that 10-round mags are standard, but larger aftermarket options may not be legal everywhere.

What's in the box?

You receive the complete rifle with one 10-round CMMG-branded magazine, the installed CMMG Zeroed muzzle brake, and a single-stage Zeroed trigger pre-set to 4.5 pounds pull weight. CMMG includes their standard AR-style hard case, a chamber flag, and documentation covering warranty registration and safety notices—but no optics, sling, or cleaning kit are included. Total package weight shipped is approximately 12 pounds in the box.

Is the CMMG Resolute MK4 worth it at $1,554.99?

At this price, it’s competitively positioned against custom-built .338 ARC uppers but offers full-rifle warranty support and out-of-the-box zero retention that home builds can’t match. For hunters transitioning from shotgun slug systems or .308 bolt-actions, the ballistic jump justifies the cost, though reloaders will find the most value given ammunition expenses. If you need a suppressor-host-ready, large-bore semi-auto without NFA paperwork, this is one of few production options available.