Mis feeding how?
Not picking up the top round from magazine?
Double feeding?
Cartridge not extracting or ejecting and next round stripping and jamming?
How much back and forth play in mag?
How much side to side play?
Have you tried different ammo?
Have you tried a different mag?
Is your bolt carrier binding?
Does you gas piston have a little play in it like should?
Have you tried cleaning and lubing the gun?
Have you looked at you receiver to see if it is bowed inwards or heavy wear marks?