Ok, so heres my deal and setup....
i built a S-12 last winter and just got around to test firing her .....the MD ARMS 20 rd mag feeds w/ no issues and so does the stock 5rd mag..... it will not cycle the Federal ammo or the PDX ammo i ran through it... i tried to adjust the MD ARMS V-Plug on all 5 settings and still wont cycle the next round into the chamber or eject the shell with either mag or ammo ... it was CeraKoted so i cleaned the gas tube and barrel really well (or so i thought).... its a really beautiful S-12...i'd appreciate any help or insight... i know i could have the gas tube