Modularity is the name of the game in the firearm industry these days, and Windham Weaponry has taken this concept to a whole new level with its new Multi-Caliber System (MCS) rifle kits.

With these rifles, you can essentially shoot more than one chambering through the same AR platform by simply changing out the barrel, magazine well and, if necessary, the bolt carrier group and magazine.

The heart of the MCS kits is a quick-change barrel system that allows you to remove/install barrel assemblies fast thanks to a latch under the handguard. Simply separate the upper and lower receivers (after ensuring the rifle is empty of course), remove the bolt carrier group and charging handle, pull the handguard latch to remove the barrel assembly—which includes the barrel, gas block and gas system—and install your desired chambering.

While the rifle is disassembled, you can replace the magazine well by removing the triggerguard detent pin and pressing on the magazine release, which allows the entire mag well to slide out of position. Simply reverse the process to install a new one.

Windham is currently offering three MCS kits that allow you to go from 5.56mm NATO to 300 BLK, 7.62x39mm and 9mm.

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