CMMG Receiver Extension MK4 Black Steel AR Platform 55CA9D7

CMMG's engineering team finely tuned the company's line of Mk4 rifles to ensure that they're one of the most reliable, finely made ARs on the market today. However, that tuned construction means that the Mk4  platforms are built with a few components designed specifically for this rifle, like the receiver extension.

Whether or not you're looking to upgrade your CMMG Mk4 or you're looking to build a faithful recreation of the company's factory rifles, the CMMG Mk4 Receiver Extension is built exactly the same way with the same attention-to-detail as the company's factory-built rifles.