Need help with diassembling Norinco M1897 12 Ga.shotgun.  I followed instructions for a Winchester to no avail.   Removed two screws and a pin. Carrier is supposed drop out ,Then bolt is removed to rear. Tried this and nothing moves.  My bolt binds in frame midway to rear and takes a good pull to work the action. Iwould like to slick it up a bit.  Horsefeathers.