I have a Model 17 Remington 20 guage pump shotgun,that has me baffled. If I hold the straight like I'm going to shoot it,the action works fine ,if the gun is held with the muzzle pointing upward the action works fine .If I
point the muzzle towards the ground,I can not get the action open. I can pull all I want on the forearm but it will not slide rearward,tip the gun up and the action works.Aside from not shooting towards the ground(haha) Any suggestions on what the problem could be---Thanks for any help --1Longbow

The operating arm has to travel back so far to allow the bolt carrier enough movement to retract the bolt lug from it's position in the reciever. Without the benefit of actually handling the piece, I would have to guess and say it could be wear in the bolt carrier, the operating arm or, both. With the gun horizontal or muzzle up, the weight of the carrier is to rear and thus the bolt carrier is several thousandths ahead of the game. Let me know what you find out.