Carefully watch as you are trying to feed a cartridge from the magazine and look to see if the case rim is coming up smoothly behind the extractor claw and the case head onto the bolt face. Your rifle may have had the extractor replaced but not fitted up properly.

A careful stoning of the bottom toe of the extractor on my Mauser 404 had the cartridges feeding like a hot knife through butter whereas before they were a pig to fed from the magazine and the cases were scratched to hell.