i always clean it every time when ive been out,come home strip it down clean it and oil it lightly.and i get it serviced and checked over once a year by my local gunsmith.ist mostly to do with the gases that are recycled from the cartridge.not enough to help the gun eject tidy,another problem is that sometimes is that where you got the end of the cartaridge and its folded over to keep the shot in,sometimes when the shot is fired and the cartaridge is about to eject it catches and jamms up,ive notice if i use a sorter cataridge i get over this problem.