Good info guys, need some help here myself.. have texas single feed 9, maybe 1st mistake, but have both lage uppers... mk2 has recon ord. mags that work with varying success, some had feed lips cut back when purchased, have used only white box win. and doesnt run great... mags are numbered and keep notes on tape on them.. only shot 10/31 once made it thru 3 soumis and had to quit, was chewing brass like a meat grinder and got one stuck so had to quit.. fun when it works but really aggravating...