None of the experts are answering, so I’ll dive in as an amateur. Is the action locking up before it fully closes, or is it locking closed? Have you tried more than one brand of ammo or bullet type? I have a 99C in 243, and it came to me with a loose fit between the lever cam and the bolt follower (Nomenclature is assuredly incorrect). I also had issues with tweaked sheet metal bits. Has yours been fiddled with?
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