Mega Arms GTR-3S AR15 Billet Lower Receiver Review

Mega Arms GTR-3S AR15 Billet Lower Receiver Review

Once you have your first AR15, you start to have the urge to build up your own AR via a kit, via individual parts, or at least upgrade the cool factor of your current AR. At some point the ultimate word in upgrade hits your lips... “Billet”.  As you may know most AR15/M4 upper and lower receivers are mad…