SIG-Mauser M2 slide issue

a friend of mine won a Sig-Mauser M2 at a Friends of the NRA banquet about 9 or 10 months ago. its in .45, and he says the last time he fired it the slide would move forward if you struck the magazine with decent pressure. anyone else heard of problems like this in Sig pistols, or is this just isolated?


Whenever you find a man who says he doesn't believe in a real Right and Wrong, you will find the same man going back on this a moment later.
--C.S. Lewis