We are working on a historical series about the origins of the Army Sniper Program and XM-21 during the Vietnam War. We have pulled together some of the timing of pre-1965, the involvement of ACTIV and the decision that was made in 1967. We have also pieced together some of the “missing...

I’m getting Leon’s XM21 in this week and am very interested in utilizing a gas-lock sight for backup iron with a low profile peep at the rear. Is this possible? How tall is the gas lock sight compared to the receiver picatinny? Any insight on this would be appreciated!!! Pic is Leon’s pic I...

In my research inspired by reading some of the threads on here I've stumbled upon the Bula Defense XM21 Receiver. I've got a simple question, I think, that can be answered preferably by someone with hands on experience, maybe Tony? Is the XM21 supposed to to; A) be a very convenient option...