First Look: Matador Arms Mag-X P320 Magazine Block

posted on May 18, 2019

The popularity of AR-style firearms in centerfire pistol calibers has greatly increased in the past few years, thanks to a variety of reasons. As 9mm ammunition is less-expensive than centerfire rifle rounds and also can be shot with less recoil, shooters have taken to AR-style pistol-caliber carbines for competition, self-defense and range use. This new boom led to many new accessories designed to allow AR owners to make use of different magazines to feed these popular platforms.

In general, the magazine types for pistol-caliber ARs fall into one of two categories: 9mm Colt-style magazines, which are dedicated 9mm AR-15 magazines, and larger capacity magazines originally designed for Glock pistols. While those options work for many people, many others have lots and lots of magazines for guns that are not a Glock or a 9mm Colt AR.

Now from Matador Arms comes a third option: The Mag-X magazine block, which allows you to use the magazines from a SIG Sauer P320 to feed your pistol-caliber AR.

The Mag-X magazine block slides into the magazine well of any mil-spec AR-15 lower receiver. No modifications are required to use the Mag-X with either the lower or the P320 magazine, and the Mag-X installs in mere seconds. The built-in magazine release on the Mag-X has locks into place and connects to the standard AR-15 magazine catch, allowing you to quickly get up and running with your P320 magazines in your pistol caliber AR. The Mag-X is manufactured from aircraft-grade aluminum with an anodized finish, and the ejector and magazine catch are both steel.

The Mag-X is available for sale throughout North America. Made in Canada, the Mag-X ships to USA customers directly from Matador’s warehouse in the USA. MSRP is $149.99 in US dollars, with special introductory pricing available.

For more information on the Mag-X, P320, visit


Rock River Arms Operator
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