NEW: CMMG DISSENT Bufferless AR Pistol Hands-On (5.7x28mm)

It’s HERE: DISSENT, the all-new bufferless AR pistol from CMMG! In this story, I’ll go in-depth with DISSENT to show you this new platform, recall shooting impressions, and share in-depth data and specifications. This is going to be fun!


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DISSENT Overview

From the CMMG Product Page:

Pistol, DISSENT, Mk4, 5.7x28MM, 6.5″
Challenge convention, the CMMG® DISSENT™ in 5.7x28mm is here to change the way you look at Personal Defense Weapons. One of the biggest challenges AR15 platform PDWs face is the buffer tube, a necessity that always adds to the overall footprint until now. The DISSENT eliminates the need entirely by employing our patent-pending Compact Action that also works hand in hand with our renowned Radial Delayed Blowback™ operating system. In addition to containing the entire action and recoil system in a more compact package, every DISSENT features a forward non-reciprocating side charger, interchangeable from left to right, allowing shooters to charge the weapon while staying focused on target. Available in your choice of custom Cerakote finish, every DISSENT comes with a 5” M-LOK® handguard and a 1913 picatinny rail at the rear to attach the pistol brace or stock* of your choice so you can make the DISSENT fit you.

TriggerTech AR-D 2-Stage Trigger
TriggerTech’s AR-D trigger was developed in collaboration with CMMG to be fully optimized for use with DISSENT firearms and upper receiver groups. With a 4 lb pull weight, the AR-D trigger showcases a light, repeatable break. CMMG does not guarantee optimal DISSENT functionality with Mil-spec or other aftermarket triggers.

Lifetime Quality Guarantee
We aim to please, that’s why every CMMG product is backed by our Lifetime Quality Guarantee against material and workmanship defects. Learn More.

*NFA Rules May Apply
Each DISSENT is shipped in pistol configuration, adding a stock will make your DISSENT an SBR and subject to NFA rules. Learn more about NFA rules.

What’s In the Box

My pre-production CMMG Pistol DISSENT included the following:

  • DISSENT 5.7x28mm bufferless AR Pistol
  • Two 32 round CMMG 5.7x28mm AR-15 mil-spec magazines
  • Instructions
  • Lock

Shooting the DISSENT in 5.7x28mm

After taking the first few shots I thought to myself: “that’s way more controllable than I thought it would be”. Shooting an AR pistol can be a bit wild- I’ve shot AR pistols chambered in 5.56 with buffer tube but no brace or stock and have found that it can be intense, and not as controllable as I would like- not the case with DISSENT. It was easy to engage targets out to 50+ yards with this AR pistol.

After shooting the DISSENT as it came in the box, I decided to attach my new BANISH 223 suppressor from Silencer Central. This makes for a still-compact and maneuverable package:

The Banish 223 is a light-weight suppressor, and didn’t cause any balance issues: but it definitely helped in the muzzle blast department! Point of impact was not affected in a measurable way, and it was very controllable even when rapid firing while moving.

DISSENT: The Ultimate Truck Gun?

My first thought after shooting the dissent with and without a suppressor was: “this could be the ultimate truck gun”.

So we did a quick scenario walkthrough using my trusted 2001 Dodge 3500 1 ton turbo diesel dually truck.

When I think about a truck gun, I’m thinking about the following:

  1. Stopping power
  2. Capacity
  3. Compactness
  4. Flexibility and capability

The DISSENT scores very high on these criteria. During our “test drill” it could not have fit the truck scenario better. The only question I have is following-up on how to safely secure the DISSENT. I’m thinking a kydex holder mounted on the tunnel could be great. If you have thoughts on this, please leave a comment!

Federal American Eagle 40 grain 5.7x28mm Performance

I would have liked to have tested multiple SKUs of ammunition with the DISSENT, but we could only find one type here locally in time for this story!

From the Federal Premium product page:

We shot 5 shots over the Caldwell G2 chronograph, and observed the following data:

Given that we have a longer barrel (6.5″ compared to the 4.8″ test barrel from Federal) it makes sense that we got a bit more velocity compared with the manufacturer’s published data.

Spotlight: Radial Delayed Blowback

The DISSENT features Radial Delayed Blowback (RDB). From our in-depth story on this technology:

Radial Delayed Blowback is a proprietary AR-platform technology developed by CMMG for PCC and related platforms. From the CMMG website:

A prime example of our Aim To Be Different mantra is our patented Radial Delayed Blowback system. The Radial Delayed Blowback system paved the way for larger caliber PCCs in an AR platform. Radial Delayed Blowback allows reliable operation without a heavy bolt, buffer or spring. The mechanical delay allows pressure to fall in the chamber before it unlocks. The system means less recoil, increased accuracy, and better velocity when using a suppressor. We started with .45 ACP and additionally, we offer 10mm, .40 S&W, 5.7x28mm and 9mm in our BANSHEE line.

This picture from the patent is a great visual showing how the chamfered lugs on the bolt are arranged:

As a part of the blowback action, these chamfered lugs unlock (as a part of rearward movement) and compress the internal spring which is seen in the above image. This gives the gas system more time to work and to lower pressures. The smoother action under recoil helps to prevent rounds of ammunition from “bouncing” out of the magazine during the cycling of the action.

Field Stripping DISSENT

Field stripping the DISSENT could not be easier:

  1. Unlock the pins
  2. Remove the upper from the lower
  3. Pull the bolt and guide rods out the back

That’s it! To re-assemble, it’s just the reverse of disassembly!

TriggerTech/CMMG AR-D Trigger on the TriggerScan

A big selling feature of the DISSENT pistol is the new AR-D trigger jointly developed by CMMG and TriggerTech (manufactured by TriggerTech). Like with all of our gun reviews, we put the DISSENT on the TriggerScan TS-11 and couldn’t believe what we saw!

In the above graph you can see three successive passes with the TriggerScan, almost an exact superimposition each time! This is the most consistent trigger we’ve tested to date. Wow.

And the data shows just how consistent this trigger is:

What’s Next

This first experience with the DISSENT has been a lot of fun, and we have some great ideas regarding what to do next with this AR pistol! Some of these ideas include:

  1. Comparing 5.7x28mm to 4.6x30mm (see our in-depth review on the “Four Six”)
  2. Testing additional optics and sights
  3. Testing recoil with the 5.7x28mm DISSENT on the Ultimate Reloader Recoil Rig

Let us know what you think we should do next with DISSENT, please leave a comment!

Get Yours

The DISSENT (5.7x28mm, 5.56, and 300 Blackouut) is available directly from CMMG (through your FFL) at:

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