CMMG DISSENT MK4 .300 AAC Blackout 16.1 in
About this product
The CMMG DISSENT MK4 .300 AAC Blackout 16.1 in is a purpose-built, tunable rifle system engineered specifically for the .300 AAC Blackout cartridge's wide operational envelope. This isn't a parts-bin AR disguised as a Blackout platform; it's a ground-up design focused on managing the 300 BLK's dual personalities. CMMG's DISSENT line addresses the specific gas and cycling requirements that plague many off-the-shelf conversions.
What is the CMMG DISSENT MK4 used for?
The DISSENT MK4 is primarily used as a multi-role carbine optimized for suppressed and supersonic shooting. Its tunable gas system and 16.1-inch barrel are engineered to cycle everything from 110-grain supersonic hunting loads to 220-grain subsonic rounds without changing buffers or springs. This makes it effective for hunting medium game under 200 yards, tactical training with a suppressor, or as a capable, over-the-counter alternative to an SBR for home defense where 16-inch barrels are required.
How does the CMMG DISSENT MK4 compare to the Stevens 334 Rifle?
The DISSENT MK4 is a semi-automatic, AR-style platform engineered for suppressed versatility, while the Stevens 334 Rifle is a bolt-action hunting rifle focused on precision at longer ranges. The Stevens 334 in .308 Win will deliver superior accuracy past 300 yards and is better for open-terrain hunting, but the DISSENT MK4 offers faster follow-up shots, superior accessory modularity, and is specifically tuned for suppressor use with subsonic ammunition.
What does it weigh and what are the dimensions?
The rifle weighs 7.3 pounds unloaded, which is about a half-pound heavier than many standard 16-inch AR-15s due to its steel barrel and beefed-up bolt carrier. Its overall length extends from 27.6 inches with the side-folding stock collapsed and folded to 37 inches with the stock fully extended and locked, giving it a collapsed profile comparable to some 10.5-inch SBRs. The handguard measures 12.5 inches long with full M-LOK attachment points on three sides.
Who is this NOT for?
This rifle is not for budget-minded buyers seeking a plinking-only 5.56 rifle or those committed to maximum long-range precision. At $2,089.99, it's a specialized tool, and its value is lost if you never intend to run it suppressed or experiment with subsonic loads. For someone who just needs a reliable hunting rifle, a Stevens 334 in .243 Win delivers excellent accuracy for several hundred dollars less.
What's in the box?
The rifle ships with one 30-round PMAG, the CMMG Zeroed muzzle brake installed, the ambidextrous safety selector, and the necessary tool for adjusting the gas block's six-port setting. Notably, it does not include iron sights, a sling, or a suppressor—you're buying the core platform. The side-folding stock is pre-installed and requires zero assembly beyond attaching an optic and loading magazines.
tuned gas system and ambidextrous controls, justify a price tag over $2,000? Absolutely, but only for the shooter who will use its specialized capabilities. If you plan to run exclusively supersonic, unsuppressed ammunition, a standard AR-15 in .300 BLK from another manufacturer will save you roughly $700. For the shooter who owns a .30 caliber suppressor and wants a rifle purpose-built to exploit both the subsonic and supersonic potential of the .300 Blackout round, the DISSENT MK4's engineering and out-of-the-box tuning make it worth the investment.Specs at a glance
Video review
Pros & cons
What works
- Tunable 6-position gas block allows precise cycling for supers, subs, suppressed, or unsuppressed.
- Side-folding stock reduces stored length to 27.6 inches—shorter than many SBRs with braces.
- Ambidextrous bolt release, safety, and magazine catch provide true left/right-handed operation.
- Weighs 7.3 lbs—a balanced weight for a 16-inch steel-barreled rifle with a folding mechanism.
Trade-offs
- Proprietary receiver set—you cannot use your existing AR-15 lower, locking you into the CMMG ecosystem.
- No iron sights included—adds an immediate $100-$250 expense for backup sights or an optic.
- The Zeroed muzzle brake is loud and concussive; most users will immediately replace it with a suppressor mount or linear comp.
Expert review
Key attributes
| upc | 810144721491 |
| manufacturer | CMMG |
| manufacturer part number | 30A750AMB |
| barrel length | 16.10" |
| caliber/gauge | .300 AAC Blackout |
| capacity | 30 + 1 |
| safety | CMMG Zeroed 60/90 Degree |
Frequently asked questions
- Is it compatible with a standard AR-15 lower receiver?
- No, it is not. The CMMG DISSENT MK4 uses a proprietary upper and lower receiver set designed around its radial-delayed blowback operating system. You cannot drop this upper onto your existing Mil-Spec AR-15 lower; it must be purchased as a complete rifle.
- Does it work with a .30 caliber suppressor?
- Yes, its 5/8x24 threaded muzzle is the standard thread pitch for .30 caliber rifle suppressors like those from Dead Air, SilencerCo, or SureFire. The adjustable gas block is crucial for mitigating excess gas to the face when shooting suppressed with subsonic rounds.
- Can I use standard .300 Blackout AR-15 magazines?
- Yes, it feeds reliably from any Magpul PMAG or Lancer L5AWM magazine designed for .300 AAC Blackout. These magazines are typically marked with .300 BLK identification to prevent accidental loading into a 5.56 rifle, which is a critical safety feature.
- How long does shipping take to an FFL?
- Ironclad Armory processes in-stock items within 1 business day. Transit time via FedEx or UPS Ground to a continental U.S. FFL typically adds 3-7 business days. You must contact your chosen FFL dealer to arrange the transfer before completing your purchase.