had a issue with this today . tried all sorts of ammo ...... and it was stovepiping. then it would work fine then again out of the blue it would start again at times it was every other round  .......

I hoping to tear it down tonight and hope the issue was that I used milspec grease to lube parts and the grease would cause something to stick.. doubtful ....

the only thing I done recently was install a new firing pin... it all went back together fine .....

if anyone else had this problem and fixed it .. please inform me please.....

you may want to look at the ejector shield thru an open bolt .... make sure that the extractor plate is in the SECOND hole not the first .... the first hole should be open.

that would be it ................