CMMG Dissent Mk4 SBR 5.56 NATO
Model: 55AF50F
CMMG Dissent Mk4 SBR 5.56 NATO
Model: 55AF50F
Full Specifications
Threaded 1/2x28 barrel: compare 5.56 / .223 suppressor prices.
About This Firearm
The CMMG Dissent Mk4 SBR is a direct-impingement 5.56 NATO short-barreled rifle built for truck or pack gun use. It has an MSRP of $2,049.95. Its bufferless Compact Action leaves no buffer tube behind the receiver, so the B5 Systems Modular Platform stock folds alongside and the package comes down to 16.5 inches.
An M-LOK handguard with a top Picatinny rail takes an optic and a light, and the ZEROED drop-in trigger and 60 or 90 degree safety selector are fitted at the factory. The rifle weighs 5.6 lbs and opens to 26 inches, and the ZEROED linear compensator unscrews from 1/2x28 threads for a suppressor.
If you're cross-shopping, the SIG Sauer MCX Rattler LT SBR has an MSRP of $2,519.99, a 7.75 inch barrel and 6.2 lbs, and it folds too, though its muzzle is threaded 5/8x24 where the CMMG uses 1/2x28. The IWI Tavor X95 SBR has an MSRP of $1,999 and fits a 13 inch barrel inside a 22.8 inch bullpup, so it keeps velocity in a short rifle, but it weighs 7.5 lbs and never gets shorter.
Best For
Strengths & Limitations
- The lower is a forged Mk4 AR-pattern receiver, so grips and trigger parts come off the AR shelf.
- Cerakote is offered in Armor Black, Coyote Tan, Midnight Bronze and Tungsten at one price.
- The trigger is a drop-in cassette, so swapping it later is one part and two pins.
- CMMG lists the gas block as non-adjustable, so the back pressure a suppressor creates is whatever the system gives you.
- A 6.5 inch barrel costs real velocity in 5.56, which shows up as less reach than a carbine has.
- The Compact Action upper is CMMG design, so a standard AR buffer tube, carbine stock or recoil spring does not fit it.
Compatible Ammunition
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Frequently Asked Questions
Does it take standard AR-15 magazines?
Yes. It feeds AR-pattern 5.56 magazines, and two CMMG 30-round magazines come in the box.
How does it differ from the CMMG Dissent Mk4 in .300 Blackout?
That one is a 16.1 inch rifle in .300 Blackout at 6.4 lbs with a 5/8x24 muzzle. This is the 5.56 short-barreled version of the same Compact Action, with a shorter barrel and a smaller thread.
Does an optic have to come off to fold the stock?
No. The rail is on the upper and the stock folds to the side of the receiver, so an optic stays mounted and keeps its zero through the fold.
