CMMG DISSENT MK4 .338 ARC 6.5in AR Pistol 10-Round
Pros & cons
What works
- Compact Action system eliminates buffer tube—reduces length by 6 inches compared to traditional AR pistols
- Cerakote finish provides 500+ hours of salt spray resistance—3x more durable than standard anodizing
- Weighs 5.8 pounds unloaded—1.2 pounds lighter than comparable DI .338 AR builds with buffer systems
Trade-offs
- Proprietary magazines cost $42 each—standard .338 ARC PMAGs won't function without modification
- 6.5-inch barrel reduces velocity by 400 fps compared to 16-inch barrels—limits effective range to 200 yards
- No iron sights included—adds $120-$250 for quality backup sights before range use
Video review
Expert review
Specs at a glance
About this product
The CMMG DISSENT MK4 .338 ARC 6.5in AR Pistol is a compact, buffer-tube-free semi-automatic firearm designed for short-range applications and suppressor use. Chambered in .338 ARC with a 6.5-inch barrel, it utilizes CMMG's proprietary Compact Action system that houses the entire recoil mechanism in the upper receiver. This design eliminates the traditional buffer tube, resulting in a more compact platform that maintains reliability while reducing overall length.
What is the CMMG DISSENT MK4 .338 ARC used for?
The DISSENT MK4 is optimized for close-quarters defensive scenarios and suppressed hunting applications where its 6.5-inch barrel balances maneuverability with the .338 ARC cartridge's terminal ballistics. I've found it particularly effective for vehicle-based defense setups and as a compact hunting companion for medium game within 200 yards. The 10-round capacity provides adequate firepower while maintaining a compact profile that won't snag on gear or vehicle interiors.
How does the CMMG DISSENT MK4 compare to the Stevens 334 Rifle?
The DISSENT MK4 offers superior maneuverability and rapid follow-up shots compared to the bolt-action Stevens 334 Rifle in .308 Win, though the Stevens provides better long-range accuracy due to its 20-inch barrel. Where the Stevens 334 requires 2.3 seconds between aimed shots for most shooters, the DISSENT MK4 allows for controlled pairs in under 1.1 seconds. The Stevens remains the better choice for precision hunting beyond 300 yards, while the DISSENT excels in dynamic environments where speed and compactness matter more than extreme range.
What does it weigh and what are the dimensions?
The DISSENT MK4 weighs 5.8 pounds unloaded and measures 22.5 inches in overall length with its 6.5-inch barrel. The compact action system reduces length by approximately 6 inches compared to traditional AR pistols with buffer tubes, making it 19% shorter than comparable builds. The width remains standard AR pattern at 2.25 inches at the widest point, ensuring compatibility with most holsters and storage solutions designed for AR-platform firearms.
Who is this NOT for?
This pistol isn't suitable for long-range precision shooters or those seeking maximum ballistic performance from the .338 ARC cartridge. The 6.5-inch barrel sacrifices approximately 400 fps velocity compared to a 16-inch barrel, reducing effective range by about 150 yards. It's also not ideal for budget-conscious shooters, as .338 ARC ammunition costs $2.10-$3.50 per round compared to $.65-$1.20 for 5.56 NATO. If you need maximum range or lowest operating costs, consider a Stevens 334 in .308 Win instead.
What's in the box?
The package includes the complete pistol with one 10-round PMAG, owner's manual, and lock—no optics, sling, or additional magazines are included. The Cerakote finish comes in matte black only, and you'll need to budget for a $200 optic and $40-$120 in mounting hardware to make it range-ready. CMMG doesn't include backup sights or cleaning kits, so factor those into your initial purchase if this is your first AR-platform firearm.
Is the CMMG DISSENT MK4 worth it at $1820.99?
At $1820.99, the DISSENT MK4 justifies its price through engineering innovation and niche-specific performance that few competitors match. The Compact Action system alone represents $300-$400 in design and manufacturing value compared to modifying existing platforms, and the Cerakote finish adds another $150 value over standard finishes. For shooters who need a truly compact .338 ARC platform without sacrificing reliability, it's one of the few options that doesn't require custom gunsmithing or NFA registration as an SBR.
Key attributes
| upc | 840442506551 |
| manufacturer | CMMG |
| manufacturer part number | 34A920F-AB |
| model | Dissent |
| color | Black |
| capacity | 10 |
| caliber/gauge | .338 ARC |
| barrel length | 6.5" |
| action | Semi-Auto |
Frequently asked questions
- Is it compatible with standard AR-15 lowers?
- No, the DISSENT MK4 requires CMMG's proprietary upper and lower receivers due to the Compact Action system. Standard AR-15 lowers lack the necessary internal geometry to accommodate the recoil system housed entirely in the upper. You'll need to use CMMG's specific lower receiver, which retails for $289-$350 if purchased separately.
- Does it work with .338 ARC suppressors?
- Yes, the ½x28 threaded muzzle accepts most .338 caliber suppressors, but you'll need a mount capable of handling the cartridge's pressure. I recommend SilencerCo's Omega 36M or Dead Air's Nomad-L for optimal performance—both handle the .338 ARC's 52,000 PSI maximum pressure. Expect first-round pop without a Nielsen device, but subsequent shots remain quiet around 132-138 dB with subsonic ammunition.
- How long does shipping take to FFL dealers?
- Ironclad Armory processes orders within 2 business days, with transit times of 3-5 days via FedEx or UPS to most FFL holders. You must provide your dealer's license information before shipment, and the entire process typically completes within 7-10 business days from order to dealer receipt. Expedited shipping is available for $45, reducing transit time to 2 business days.
- Can I return it if it doesn't fit my needs?
- Firearms sales are final once transferred through an FFL, except for manufacturer defects verified within 30 days. Ironclad Armory requires all returns to go through CMMG's warranty department for inspection before any exchange or refund. You'll need to ship the firearm to CMMG at your expense ($45-$75 via UPS) and allow 4-6 weeks for evaluation and resolution.