First Look: CMMG 5.7x28 mm AR Conversion

by
posted on January 15, 2020
** 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-inc-57x28mm-ar-conversion-magazine-upper-receiver-f.jpg
In 2020, the 5.7x28 mm cartridge is coming back in a big way, and CMMG joined multiple companies in offering a new option for fans of this high-velocity cartridge. Following up on the success of the company's Banshee chambered in 5.7x28 mm, CMMG now offers an AR-15 conversion package that allows shooters to mate their mil-spec AR-15 lower receiver with the company's 5.7x28 mm Radial Delayed Blowback upper-receiver group.

The key to this conversion lies in CMMG's 5.7 AR Conversion Magazine, which is designed to fit into standard AR-15 magazine wells while providing a reliable feed mechanism that's compatible with the company's 5.7x28 mm upper receiver. To convert any standard AR-15 to a 5.7 mm firearm, simply remove the existing upper-receiver group and replace it with a compatible, 5.7x28 mm upper receiver from CMMG. Once the upper receiver is installed, users can simply insert a CMMG 5.7 AR Conversion Magazine into the mil-spec magazine well.

In addition to allowing AR owners to experiment with the 5.7x28 mm cartridge without having to purchase an entirely new firearm, this CMMG conversion system maintains the controls and configuration of any existing AR-15 lower. If users have an enhanced trigger installed in their gun or optimized controls, they can continue using those components without having to invest in or learn an entirely new firearm. CMMG recommends the use of a standard carbine buffer and action spring to run the 5.7x28 mm conversion reliably, and the magazine provides last-round bolt hold-open capability.

A complete lineup of CMMG Banshee and Resolute upper receivers are compatible with the 5.7 AR Conversion Magazine. CMMG's Mk57 upper receivers can be had in 5", 8" and 16" barrel lengths, and the uppers ship complete with bolt-carrier group and charging handle. A single CMMG 5.7 AR Conversion Magazine holds 40 rounds of 5.7x28 mm, and the suggested retail price on the mag is $39.95. Suggested retail pricing on the Mk57 upper receiver complete with three 40-round magazines starts at $799.95. For more information on these conversion kits, visit cmmginc.com.


Latest

TU 33 Studio01
TU 33 Studio01

The Norinco TU-33/40: A Rimfire Mauser Lookalike from China

The Norinco TU-33/40 is, at a glance, a copy of a Mauser 98k with a few choice details that give away the fact that it’s not a big-bore World War II workhorse.

AI Tools Enter the Used-Gun Market

Companies that deal in the used-gun market are not shy about sharing the advantages their AI-driven tools and services.

Standing Guard | Standing on the Line for Freedom

This past August marks 46 years since I raised my right hand and was commissioned as an infantry officer in the United States Marine Corps. In the summer of 1980, I entered active duty with a firm sense of civic duty and a deep desire to serve our great nation. Like so many who wear the uniform, I was ready to contribute directly to the defense of freedom.

Making Baschieri & Pellagri Shotshells

Italy is known for its many makers of fine-quality shotguns, but what many might not known is that Italy is also home to one of the industry's top manufacturers of shotshells for hunting and sporting use: Baschieri & Pellagri.

Rifleman Interview: Volquartsen Firearms

Several of Volquartsen’s excellent rimfire firearms were on display at “Plinkapalooza” earlier this year.

Army Purchases EOTECH Electro-Optics

EOTECH recently announced that the U.S. Army had purchased 14,000 of its lasers, holographic optics and magnifiers for use on the military's M7, XM8 and M250 platforms.

Interests



Get the best of American Rifleman delivered to your inbox.