I'm not 100% sure I understand your problem. It sounds like the extractor cam or barrel stop as you refer to it is loose in the knuckle. Is yours not screwed in? Many of them are, some are not.
If it is fit into a slot and loose in the slot it would need to be removed, built up via TIG welding and refit. The barrel stop should have no relationship to how tight your fore end is. If the fore end is loose on the knuckle it needs to be pushed further back towards the breech face. To do this the fore arm lug needs to be either moved back(they often become loose and are not put back in the proper spot), or built up again via careful Tig welding. Just because you can not move the fore end for and aft does not mean it is tight enough. I hope this helps a bit.
Steve

Firearms imports, consignments


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