My S-12 is having issues with ejecting the spent shell. It extracts with no problem but does not release the shell, usually the bolt recloses causing a double feed but on the last round in the mag the bolt will reclose inserting the spent shell back into the chamber. I've looked over the forums but haven't seen anything like this. It seems most peoples issues are fail to extract.
I bought the gun used, and had to drill out the gas ports to get it to run. It was an auto plug to vent excess gas, but even when I closed it all the way (no venting) it still wouldn't release. Even manually