A growing number of AR-15 type uppers have a self-contained recoil system that doesn’t need the traditional buffer assembly / receiver extension on the lower receiver. This opens up even more “stock options” for these guns. The KNS Precision AR / MCX Stock Adapter makes it easy to install an M1913 Picatinny-mount stock on a standard mil-spec AR-15 lower receiver. Brownells Gun Tech™ Caleb Savant walks us through the installation steps. The KNS AR / MCX adapter kit includes a threaded plug that screws into the lower receiver in place of the receiver extension (aka “buffer tube”), recoil buffer, recoil spring, and buffer detent. An M1913 rail section then slides into the slot on the rear of the plug and locks down via the included washer and screw. The kit is available with two versions of the rail section; Caleb explains which situations require which rail section. Got a Brownells BRN-180, SIG Sauer MCX / MPX, Foxtrot Mike FM-9 / FM-15 Gen2, or CMMG .22 conversion upper and a standard mil-spec AR-15 lower? The KNS AR / MCX stock adapter is your ticket to mounting a JMAC Customs stock, the Midwest Industries Side-Folding Extruded Stock, our dedicated Brownells BRN-180 folding stock, a SIG Sauer MCX / MPX stock or brace, or one of the many other Picatinny folding stocks or braces currently available!