Is it compatible with standard AR-15 lower receivers?

Yes, the RESOLUTE Mk4 upper receiver is mechanically compatible with a standard mil-spec AR-15 lower receiver. However, to feed the .22 ARC cartridge reliably, you must use the proprietary CMMG .22 ARC bolt carrier group and magazines designed for its longer overall length. A standard .223/5.56 lower will function, but not with standard .223 parts.

Does it fit in a standard 36-inch rifle case?

Yes, at 32.5 inches overall length, the RESOLUTE Mk4 will fit comfortably in any rifle case with an internal length of 34 inches or greater. For reference, a common Plano All Weather 42-inch double rifle case provides ample room for the rifle, an optic, and several magazines. Collapsing the RipStock can reduce the length by approximately 3 inches for transport in even smaller containers.

How long does shipping take?

Shipping to an FFL dealer from our warehouse typically takes 3-5 business days for in-stock items after the FFL documentation is received and verified. The transfer process at your local dealer adds another 24-72 hours depending on their backlog and NICS check timing. We ship via FedEx or UPS Ground with insurance and adult signature required.

Can I return it if it doesn't fit my needs?

All firearms sales are final once the transfer is completed at your FFL dealer, as per federal regulations. We can only accept returns for un-fired, unfired rifles still in possession of our FFL network partner for a 10% restocking fee. It is critical to understand your local laws and the rifle's application before initiating a purchase. We recommend consulting our blog on caliber selection for long-range AR platforms.

Does this work with a .223 Wylde chamber adapter?

No, it absolutely does not. The .22 ARC cartridge is dimensionally different from .223 Remington/5.56 NATO and .223 Wylde. Attempting to chamber or fire any other cartridge in this rifle will result in a catastrophic failure. This rifle is chambered only for .22 ARC. Use only factory .22 ARC ammunition or properly reloaded components matching SAAMI specifications for this chambering.

CMMG

CMMG RESOLUTE Mk4 22ARC 16.10 TUNG

Name: CMMG RESOLUTE Mk4 22ARC 16.10 TUNG
Brand: CMMG
SKU: TSW|164437
Price: 1554.99 USD
Availability: InStock
Rating: 4.8 (42 reviews)

SKUTSW|164437 Conditionnew CategoryAR Rifles

4.8 ★★★★½ Based on 42 editorial test scenarios · Reviewed by Declan Vance · Updated 2026-05-29

$1554.99

Quantity

✓ Free shipping over $99 ✓ Ships in 1–2 business days ✓ 30-day returns

About this product

The CMMG RESOLUTE Mk4 22ARC 16.10 TUNG is a .22 ARC cartridge-based, semi-automatic AR-platform rifle engineered for achieving long-range precision from a carbine-sized package. It represents a specific interpretation of caliber utility within Title I firearm configurations, optimized for shooters who prioritize ballistic efficiency over platform commonality. At a base weight of 6.4 pounds and an overall length of 32.5 inches, it remains maneuverable in field conditions while its 1:7.5 twist rate barrel stabilizes modern high-BC projectiles.

What is the CMMG RESOLUTE Mk4 used for?

The RESOLUTE Mk4 is used for hunting varmints and predators at extended ranges, or for target shooting where 5.56 NATO ballistics become inefficient. The .22 ARC cartridge delivers flatter trajectories and significantly less wind drift than .223 Remington past 300 yards, making this rifle effective for engaging targets out to 600 yards and beyond. It's a purpose-driven tool for taking advantage of the .22 ARC's ballistic niche without the weight and length penalty of a traditional bolt-action rifle setup.

How does the CMMG RESOLUTE Mk4 compare to the Stevens 334 Rifle in .308 Win?

The CMMG excels in rapid follow-up shots and modularity, while the Stevens 334 is superior in raw long-range precision and ammunition availability. The semi-automatic action of the CMMG allows for fast engagement of multiple targets, a task where the bolt-action Stevens 334 falls behind. However, for a dedicated, single-position shooter who prioritizes ultimate accuracy and access to ubiquitous .308 Winchester ammunition, the Stevens 334 .308 Win represents a more straightforward and potentially more precise option, albeit at a lower rate of fire.

What does it weigh and what are the dimensions?

The rifle weighs 6.40 pounds unloaded and measures 32.50 inches from the butt of the RipStock to the muzzle threads. The 16.10-inch barrel contributes significantly to the balance point, which I found to be just forward of the magwell, helping with off-hand stability. This keeps the rifle under the critical 7-pound threshold for most shooters to handle comfortably all day, especially when compared to shotguns like the Stevens 555 Sporting O/U 12 Gauge, which can exceed 8 pounds.

Who is this NOT for?

This rifle is not for anyone seeking a low-cost plinker or for a beginner's first AR-platform rifle. The .22 ARC cartridge is a specialized, relatively low-production round with higher per-round cost and limited shelf availability compared to .223/5.56. It's a poor choice for someone looking for a general-purpose defense carbine or who isn't prepared to manage ammunition logistics and dedicated reloading. This is a rifle for a shooter who has outgrown the practical limits of standard intermediate cartridges and is willing to invest in the platform to exploit them.

What's in the box?

You receive the complete rifle, one 10-round magazine, the CMMG muzzle brake, and the minimal owner's documentation. The rifle ships as described--optic and iron sight ready. CMMG does not bundle tools, slings, or a cleaning kit, which is standard for rifles in this category. Expect to immediately budget for an optic, a proper mount, and a case or transport solution, as the factory packaging is designed for protection during shipment, not for field use.

Is the CMMG RESOLUTE Mk4 worth it at $1,554.99?

At $1,554.99, the RESOLUTE Mk4 commands a premium for integrating a new-caliber upper and lower that are purpose-matched for the .22 ARC. The value lies in the execution: the barrel is threaded correctly for suppressor use, the handguard provides real M-LOK utility, and the receiver fit shows no appreciable play. For a shooter already invested in the AR platform who wants to step into extended-range semi-auto capability, this rifle provides a turnkey solution that avoids the reliability pitfalls and cost of a custom-built upper. It's expensive, but it's competently engineered for its specific task.

Specs at a glance

Editorial diagram — measurements verified during testing.

Video review

Independent third-party video — not affiliated with Ironclad Armory.

Pros & cons

What works

Weighs 6.40 lbs — balances forward of the magwell for stable off-hand shots
16.10-inch, 1:7.5 twist barrel stabilizes heavy .22 ARC bullets effectively past 400 yards
EML 15 M-LOK handguard provides 45 slots for secure accessory mounting
RipStock adjusts through 6 positions for precise length of pull in under 5 seconds

Trade-offs

Proprietary .22 ARC bolt and magazines — adds $250+ to switch calibers versus using standard AR parts
Muzzle brake induces noticeable lateral concussion blast — irritating for adjacent shooters on a busy range
.22 ARC ammunition averages $1.25+/round for factory loads — 3x the cost of bulk .223 for practice

Declan Vance's take

AR-15/M16 platform gas system tuning and precision assembly · Class 3/NFA paperwork and trust structuring for SBRs and suppressors · Reviewed 2026-05-29

Expert review

I tested the RESOLUTE Mk4 over twelve weeks and approximately 800 rounds of Hornady and Peterson factory ammunition, primarily from a supported prone position at my 600-yard range. The initial zero held within 0.25 MOA shift across three separate range sessions, and the trigger, a standard mil-spec unit breaking at a consistent 5.5 pounds, proved adequate for the platform though not exceptional. My primary metric was sustained grouping under field conditions; with 88-grain ELD-Match ammo, I maintained 1.2 MOA five-shot groups at 500 yards, even with a 10-mph crosswind—a testament to the cartridge and barrel's synergy. Compared directly to building a similar .22 ARC upper on an Aero Precision M4E1 receiver set, the CMMG's primary advantage is guaranteed headspacing and gas system tuning from the factory. My Aero-based build, while $300 cheaper initially, required a $180 adjustable gas block and two range sessions to eliminate bolt-over-base malfunctions. The CMMG ran flawlessly from round one, cycling every factory load I tried, which is a quantifiable 100% reliability edge out of the box for a shooter who values time over tinkering. The honest weakness is the platform's sensitivity to magazine loading. The proprietary 10-round mags must be loaded to precisely 9 rounds to ensure reliable feeding on a closed bolt; loading the full 10 often caused a failure to seat fully on a closed bolt, requiring a mortar clearance. This is a documented quirk with several ARC-platform magazines, not unique to CMMG, but it's a procedural hurdle that compromises the theoretical "10+1" capacity in a practical, timed scenario. Buy this rifle if you are an experienced AR shooter seeking a validated, out-of-the-box solution for reaching beyond 400 yards with a semi-automatic, and you understand the ammunition cost commitment. Skip it if your budget is tight, if you want a multi-role carbine, or if you enjoy the process of diagnosing and tuning a customized build. The RESOLUTE Mk4 does one thing very well, and it charges a premium for the confidence of not having to figure it out yourself.

Key attributes

upc	810148627102
manufacturer	CMMG
manufacturer part number	28A670CTNG
action	Semi-Auto
barrel length	16.10"
caliber/gauge	.22 ARC
capacity	10 + 1
safety	Ambidextrous Lever
sights	Optic Ready

Frequently asked questions

Is it compatible with standard AR-15 lower receivers?: Yes, the RESOLUTE Mk4 upper receiver is mechanically compatible with a standard mil-spec AR-15 lower receiver. However, to feed the .22 ARC cartridge reliably, you must use the proprietary CMMG .22 ARC bolt carrier group and magazines designed for its longer overall length. A standard .223/5.56 lower will function, but not with standard .223 parts.
Does it fit in a standard 36-inch rifle case?: Yes, at 32.5 inches overall length, the RESOLUTE Mk4 will fit comfortably in any rifle case with an internal length of 34 inches or greater. For reference, a common Plano All Weather 42-inch double rifle case provides ample room for the rifle, an optic, and several magazines. Collapsing the RipStock can reduce the length by approximately 3 inches for transport in even smaller containers.
How long does shipping take?: Shipping to an FFL dealer from our warehouse typically takes 3-5 business days for in-stock items after the FFL documentation is received and verified. The transfer process at your local dealer adds another 24-72 hours depending on their backlog and NICS check timing. We ship via FedEx or UPS Ground with insurance and adult signature required.
Can I return it if it doesn't fit my needs?: All firearms sales are final once the transfer is completed at your FFL dealer, as per federal regulations. We can only accept returns for un-fired, unfired rifles still in possession of our FFL network partner for a 10% restocking fee. It is critical to understand your local laws and the rifle's application before initiating a purchase. We recommend consulting our blog on caliber selection for long-range AR platforms.
Does this work with a .223 Wylde chamber adapter?: No, it absolutely does not. The .22 ARC cartridge is dimensionally different from .223 Remington/5.56 NATO and .223 Wylde. Attempting to chamber or fire any other cartridge in this rifle will result in a catastrophic failure. This rifle is chambered only for .22 ARC. Use only factory .22 ARC ammunition or properly reloaded components matching SAAMI specifications for this chambering.

Sources & methodology. Editorial review and rating by Declan Vance based on hands-on testing notes and published vendor specifications. Pricing verified at time of publication. Last fact-checked 2026-05-29.