My friend has a Marstar scope mount (LP-MNT-914) on his Norinco M14. He was having issues every 4th round or so. The empty shell would bounce off the mount and back into the action resulting in a jam. The mount has taken a beating so its back to iron sights for now. Has this happened to anyone else or is this just his experience? I want a scope mount for my Norc when it arrives and I want to avoid problems.