Product Preview: CMMG 9 AR Conversion Adapters

by
posted on October 29, 2019
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
cmmg-9-arc-adapters.jpg

AR-style pistol-caliber carbines chambered for 9 mm Luger typically require the use of a dedicated 9 mm lower receiver, but CMMG’s 9 AR Conversion (9 ARC) Magazines remove that requirement by allowing any unmodified AR-15 lower to function with the company’s Radial Delayed Blowback 9 mm Luger upper receivers. And taking the versatility of the system even further, CMMG’s 9 AR Conversion Adapters allow any standard (.223 Rem.) 30-round Gen 2 or Gen 3 Magpul PMAGs to be temporarily altered for 9 ARC compatibility. Just remove the magazine’s baseplate retainer and spring, insert the CMMG adapter, compress the spring and slide the factory baseplate back into place. Capable of up to a full 30 rounds of ammunition, the adapters can also be modified to limit capacity to either 10, 15 or 20 rounds. These adapters are available for $30 each, or $80 for a pack of three. For more information, please visit cmmginc.com.

Additional Reading:
NRA Gun of the Week: CMMG Resolute 300 MK4 Rifle
NRA Gun of the Week: CMMG Mk57 Banshee
Product Preview: CMMG RipStock Buttstock Assembly
Tested: CMMG MK4 Banshee .22 LR Pistol

Latest

US Palm STORM CAT4 01
US Palm STORM CAT4 01

Storm on the Horizon: US Palm's Storm Cat4 Rifles & Pistols

Known primarily for its line of AK-platform accessories, this year, US Palm branched out with a full line of AR-style rifles and pistols, all of which have a unique feature set.

Review: Axil XCor Pro Hearing Protection

These do-it-all earbuds from Axil actually do it all.

Federal's New 6.5 Creedmoor +Peak: The Peak Alloy Case Goes Mainstream

Federal introduced its high-pressure Peak Alloy case design with the 7 mm Backcountry in 2025. Now, the company is incorporating it into high-pressure 6.5 Creedmoor loads with the +Peak design.

I Carry: Springfield Armory Echelon 4.0FC in a JM Custom Kydex Holster

In our latest "I Carry" video, a Springfield Echelon 4.0FC is outfitted with Aimpoint's new COA enclosed-emitter red-dot optic, and to carry this optic-equipped handgun, we've selected a JM Custom Kydex holster.

The Armed Citizen® June 5, 2026

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

Multi-Caliber MK24 to Replace SCAR-H For SOCOM

U.S. Special Forces will soon be replacing their 7.62-NATO-chambered SCAR-Hs with a new, barrel-swapping MK24 Mid-Range Gas Gun-Assault (MRGGA) gun capable of running either 7.62 NATO or 6.5 Creedmoor.

Interests



Get the best of American Rifleman delivered to your inbox.