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Has my order shipped?

You will receive a confirmation email when your order ships.

How do I return an item for repair?

To ensure prompt service, please navigate to the contact page by clicking here Contact. Once you have arrived at the contact page choose Tech Support from the drop down menu and add as much information as possible about the issue you are having then submit the form.

Are all CMMG products covered under the Lifetime Quality Guarantee?

Yes. CMMG, Inc. will guarantee its products against defects in material or workmanship. CMMG, Inc. will repair, replace or substitute part(s) (at CMMG, Inc. discretion) at no charge to the customer if a defect of material or workmanship is found. All service work must be carried out by CMMG Inc. Please provide a copy of the invoice or proof of purchase when submitting service work. Notice: CMMG, Inc. sells complete firearms and components. If you have received a CMMG, Inc. firearm and are not satisfied, please contact CMMG, Inc. If you suspect your firearm isn’t factory built, contact CMMG, Inc. for confirmation. Returned products that are found without a defect are subject to a restocking fee.

Who do I contact if I have a question about a product?

To ensure prompt service, please navigate to the contact page by clicking here Contact. Once you have arrived at the contact page choose Tech Support from the drop down menu and let us know what product you are inquiring about, and your question, then submit the form.

What is CMMG’s 9 AR Conversion ?

Developed in collaboration with Mean Arms, CMMG’s 9 AR Conversion magazine is designed to allow a standard M16/M4/AR15 lower to run 9 x 19mm Luger ammunition with the use of a CMMG MkGs 9mm Radial Delayed Blowback operating system upper group. The 9 AR Conversion magazine is not a .223/5.56 to 9mm conversion kit. The 9 AR Conversion allows owners of standard M16/M4/AR15 to purchase a dedicated CMMG 9mm MkGs upper group. The 9 ARC and MkGs upper groups are designed to be compatible with M16/M4 full auto lower receivers. The 9 AR Conversion utilizes a MagPul PMAG® 30/AR/M4 GEN M2 MOE® magazine body.

NOTE: The lower receiver should run a standard carbine buffer and action spring for reliable functioning.

Will a 9 AR Conversion Magazine Work in a Blowback 9mm?

No, these magazines were developed to work specifically with CMMG’s Radial Delayed Blowback operating system and do not have a fixed ejector.

What is a Mk4?

The Mk4 is our line of receivers based off the traditional Mil-Spec AR 15 receiver. They are forged from 7075 T6 aluminum, and work with standard AR style magazines.

CMMG Mk4 Platform Specifications

Buffer Tube Material – 7075 Alum. (During high demand we do supplement with 6061 Alum.)

Buffer Weight(s):

A1 = 5.2oz

Carbine = 2.952oz

H = 3.784oz

H2 = 4.6oz

H3 = 5.4oz

Bolt Carrier Group Materials:

Bolt – Steel, 9310

Carrier – Steel, 8620

Extractor – Steel, 4140 or 4340

Ejector – Steel, S-7

Currently available in the following calibers:

22LR

5.56x45mm (.223)

300 BLK

22 Nosler

224 Valkyrie

Virtual Patent Information can be found here.

What is a Mk3?

The Mk3 is our line of receivers based off the LR-308 High Pattern 308 rifles. They are made from Billet 7075 T6 Aluminum, and work with LR-308/SR25 style magazines.

CMMG Mk3 Platform Specifications

Compatibility:

CMMG Mk3 Uppers:

Typically compatible with lowers using SR25 magazines.

Not compatible with lowers using FAL magazines.

Typically compatible with DPMS Gen1 parts and accessories

Buffer Weight(s):

Rifle (A1) = 5.4oz

Carbine = 3.9oz

Bolt Carrier Group Materials:

Bolt – Steel, 9310

Carrier – Steel, 8620

Extractor – Steel, S-7

Ejector – Steel, S-7

Currently available in the following calibers:

.308 Winchester (7.62x51mm NATO)

6.5 Creedmoor

Virtual Patent Information can be found here.

What is a Mk9?

The Mk9 is our line of receivers that look like our Mk4 receivers but have a magwell made specifically to accept 9mm Colt style magazines. They are forged out of 7075 T6 Aluminum, and have the lower receiver comes with the 9mm bolt catch, feed ramp, and ejector installed. The complete firearms operate off a traditional blowback system.

CMMG Mk9 Platform Specifications

Based off of the standard Mk4 receivers

Buffer Weight(s):

Dedicated 9mm = 5.36oz (Dark grey/black, longer tham Mk4 Carbine buffer)

Bolt Group Materials:

Bolt – Steel, 8620

Extractor – Steel, 4140

Fixed Ejector – Steel, 1070

Virtual Patent Information can be found here.

What is a Mk47?

The Mk47 is the originator of our new mid-sized receiver sets. They are based off of our Mk3 receivers but have been shortened in length to a mid-size receiver. Made from Billet 7075 T6 Aluminum, and designed to accommodate AK47 style magazines, we designed the Mk47 as a mid-size system which allows us to use more robust components for cartridges that would normally push the boundaries of a traditional AR. With the Mk47, we witnessed the birth of a new AR in a mid-size system and using our Powerbolt Technology.

The Mk47 was formally referred to as the Mutant. We are no longer marketing it under this name.

Virtual Patent Information can be found here.

What is a MkW?

The MkW is our line of mid-sized receivers that are built from Billet 7075 T6 aluminum, and designed to take standard AR style magazines. With the advent of the Mk47, we found that we now had a platform that could take larger cartridges and safely fire them from a more robust system. With rounds like the .458 SOCOM in mind, we introduced the MkW as a receiver set that excels at running cartridges that are on the higher end of the pressure range for a traditional AR..

The MkW was formally referred to as the Anvil. We are no longer marketing it under this name.

Virtual Patent Information can be found here.

CMMG Mid-Sized Platform (Mk47 & MkW-15) Specifications

Buffer Weight(s):

Dedicated to Miz-Sized = 3.96oz (stamped Mk47)

Bolt Carrier Group Materials:

Bolt – Steel, 9310

Carrier – Steel, 8620

Extractor – Steel, S-7

Ejector – Steel, S-7

Currently available in the following calibers:

7.62x39mm (Mk47)

.458 SOCOM (MkW-15)

Virtual Patent Information can be found here.

What is Powerbolt Technology?

POWERBOLT Technology is a larger, more durable, AR10-sized bolt face to accommodate wider and higher-pressure cases.

Virtual Patent Information can be found here.

What is a MkG?

The MkG is our receiver set designed to take large frame Glock magazines. With so many 9mm ARs on the market, our initiation into a Glock style magazine fed AR took us straight to the .45acp. This higher pressure round led us to design the Radial Delayed Blowback operating system, and also opened up a whole new world of possibilities for future cartridges. Forged from 7075 T6 Aluminum.

The MkG is offered in .45acp (but also safely handles 450 SMC)

The MkG and MkGs were formally referred to as the Guard. We are no longer marketing them under this name.

Virtual Patent Information can be found here.

What is a MkGs?

The MkGs in our receiver set designed to take small frame Glock magazines. Based off of the MkG in .45acp, we adapted the MkG platform to operate with small frame Glock style magazine while still using our Radial Delayed Blowback operating system. Forged from 7075 T6 Aluminum.

The MkG and MkGs were formally referred to as the Guard. We are no longer marketing them under this name.

Virtual Patent Information can be found here.

What is a Mk57?

The Mk57 is our receiver set designed to take FN Five Seven (5.7×28) magazines. Continuing with the use of our Radial Delayed Blowback operating system, we found that the system lent itself to the 5.7×28 cartridge nicely. Made from Billet 7075 T6 Aluminum.

Virtual Patent Information can be found here.

Why was my Mk57 shipped with a 20rd magazine?

Through exhaustive testing CMMG found that the 20 round magazines were by far the most reliable in the Mk57.

CMMG MkG, MkGs, Mk57 Platform Specifications

Bolt Carrier Group Materials:

Bolt – Steel, 9310

Carrier – Steel, 8620

Extractor – Steel, S-7

Ejector – Steel, S-7

Currently available in the following calibers:

45ACP(MkG)

9x19mm (MkGs)

5.7x28mm (Mk57)

Virtual Patent Information can be found here.

What handguards fit my gun?

Our Mk4 handguards along with any standard AR15 type handguard should work on our Mk4, Mk9, MkG, MkGs, and Mk57 lines as the upper receivers are based off a standard Mil-Spec upper receiver.

Our Mk3 handguard along with any LR-308 High Patterned handguard should work on our Mk3, Mk47, and MkW lines.

What is DI (Direct Impingement)?

Direct impingement is a type of gas operation for a firearm that directs gas from a fired cartridge directly into the bolt carrier or slide assembly to cycle the action.

What is TB (Traditional Blowback)?

Traditional blowback is a system of operation for self-loading firearms that obtains energy from the motion of the cartridge case as it is pushed to the rear by expanding gas created by the ignition of the propellant charge.

What is Radial Delayed Blowback?

The Radial Delayed Blowback (RDB) system was created from the ground up by CMMG to eliminate problems with traditional blowback systems found in pistol caliber AR15’s. The biggest advantage of the RDB system is a gun that weighs less while simultaneously having less felt recoil.

With a traditional blowback system, the only thing keeping the chamber closed is the weight of the bolt and the action spring tension. As a result, the more powerful the cartridge is, the more weight is needed to keep the bolt closed long enough to safely operate. With the RDB system the bolt must be forced to rotate and unlock itself before it will cycle. This slows things down enough for chamber pressures to drop to safe levels ensuring reliable, and safe, operation without the need for heavy bolts or stiff action springs.

For a short visual demonstration of how the system works, please watch this video

Virtual Patent Information can be found here.

Will the RipStock/Ripbrace work on my gun?

The Standard RipStock and RipBrace is designed to work in place of a standard 6 Position receiver extension or pistol buffer tube. In the case of using it with a Mk47, MkW, or Mk3, reuse the buffer and spring from your firearm instead of using the one included with the kit.

The Micro/CQB RipStock and RipBrace is designed to replace a standard 6 Position receiver extension or pistol buffer tube with the new 5 position receiver extension. The Micro/CQB RipStock and RipBrace include a reduced size buffer to offset the shorter length. The Micro/CQB RipStock and RipBrace will NOT work with the mid-size platform of the Mk47 or MkW.

Virtual Patent Information can be found here.

What does “ALL NFA RULES APPLY” mean?

Some items we sell are more heavily regulated by the ATF. Short Barreled Rifles(SBRs) and Silencers (Suppressors) require additional paperwork before they can be delivered to your dealer, and then more paperwork and a tax before you can take possession of them.

We sell items that allow you to build either an AR Pistol, or an AR SBR. It is up to you to know your regulations, how these can impact you or your purchase, and the legal ways to own these items.

What is P3?

“P3” stands for Personal Position Preset. P3 offers multiple customizable length presets to ensure the stock or brace extends to your personal position every time it is deployed. Simply adjust the indexing screw into one of the holes to customize your preset.

Virtual Patent Information can be found here.

What is Fastback Technology?

Fastback Technology is a Patent Pending feature on certain receiver extensions that makes the RipStock and RipBrace instantly deployable and allows you to simply pull straight back to extend the stock or brace. No locking tabs to bind when dirty and no release lever like most extendable stocks and braces.

Virtual Patent Information can be found here.

Has the RipBrace been approved by the ATF?

Yes it has!

The approval letter can be found here.

I bought a CMMG conversion kit, will it work in my gun?

Our 22 Conversions are designed to work with any Mil-Spec upper receiver chambered in .223/5.56. Please note that while many AR platforms may appear to be Mil-Spec, their chambers are not, and our conversion kit will not work with them.

Our conversions will not work in any other chamberings such as 300BLK.

If you are sure that your rifle is chambered in .223/5.56 and still having problems installing it, please make sure that you have removed the rubber chamber adapter protector used to protect it during shipping.

Virtual Patent Information can be found here.

Does the .223/5.56 to 22LR conversion kit work in .223 Wylde chambers?

While the 22LR Conversion kit was designed to function in most mil-spec .223/5.56 chambers, the kit may also function in some Wylde chambers, though it may not function in all of them and is not guaranteed to function in any of them.

What steps do I need to take to turn my conversion kit into a dedicated upper group?

You will need a barrel and a barrel collar. The barrel collar replaces the chamber adapter on the conversion kit, turning it into a dedicated bolt group. Here is a link to a video that teaches you how to disassemble the 22LR kit and reassemble it.

The only difference in the reassembly portion is that you would substitute the chamber adapter for the barrel collar at that point.

I’ve lost my owner’s manual, where can I find a replacement?

You can find our complete library of Owners Manuals here and select the “Manuals” button.

How do I get a job at CMMG?

You can find our application for employment and other requirements under our Career tab here.

What model firearms are legal in my state?

With individual cities and states constantly changing ownership and purchasing laws, we highly recommend that you contact your local dealer to see if the firearm you are looking at can be purchased in your area.

How often should I clean my gun?

For Regular Shooters, CMMG recommends cleaning every 250 rounds if it is any caliber other than 22LR. In the case of 22LR, CMMG recommends cleaning every 125 rounds as 22LR ammo is particularly dirty.

For Non-Regular/Casual Shooters, CMMG recommends cleaning the firearm directly after use and making sure the firearm is dry before storing away. Leaving any kind of cleaning solution or oil/lube can cause the metal to expand (As it is a porous material), which can affect the overall functional reliability of the firearm.

Why does my magazine sometimes fall out?

If the magazine is fully loaded (to capacity) and you are inserting it on a closed bolt, the magazine does not have the opportunity to seat properly. Always insert a fully loaded magazine on an open bolt, regardless of caliber.

If it is an empty magazine, or you are inserting (loaded or empty magazines) on an open bolt, check to make sure the magazine release lever is installed correctly. More often than not, it is simply a matter of the lever and button needing one more turn/rotation to get it into proper position.

Who do I contact if my product is missing parts?

To ensure prompt service, please navigate to the contact page by clicking here Contact. Once you have arrived at the contact page choose Tech Support from the drop down menu and include where you purchased the product and what is missing then submit the form.

Do you offer a Military or LEO discount?

Yes, please email customerservice@cmmg.com with your credentials, and we will get you a code to use.