Just bought a Saiga .308 on gunbroker with a Dinzag Arsenal 2-stage trigger and a Black Poly AK stock. I plan on an ATI Tactical Grip, Muzzel Break and Aluminum Quadrail. I mostly see the 16" but I think the 308 round really needs 18+ to fully stabilize. Anyone have experience with shooting one of these with the 21.5" barrel?