Was out shooting yesterday with a friend. Had My ARs, AKs, 45 ACP& 9MM pistols, shotgun and target rifles for a workout. My 16" HBAR BM was shortstroking so did'nt get to shoot it much. When I took it home to tear it down, I remember reading from the forums about the staked key. Sure enough, one screw loosened up causing the problem.
It was a great day of shooting and showing a new friend the aspects of the assault type weapons.
So to all that post about solving possible causes of problems, thanks, for the info. It's nice to come on a forum and gather lots of useful info.