[Unclenick]

What HiBC is referring to is called positive feed. The rim surrounding the bolt face is cut away on bottom so a cartridge rim slides up into the extractor claw. A push feed bolt and extractor surround the rim completely and the extractor snaps over it whether it is magazine fed or single-loaded. A Mauser 98, for example, is a positive feed, while a Remington 600 is a push feed. A positive feed can be very hard to close on a singly-loaded round. A push feed should not be.

Marking the case is a good idea. Taking a dowel rod or a brass rod and pushing the ejector in is a good idea, though I think you would see an ejector mark on the case if that were not working correctly? I think it is more likely you will find heavy marking by the ejector, or, as discussed earlier, a headspace problem.