It sounds like the problem is wrong/bad magazines to me.
BTW: to anyone that owns a CZ-75, be careful about loading rounds singly into the chamber instead of from the magazine.
The extractor is not beveled to snap over the rim of a round placed into the chamber manually, it is made to engage the rim of a round coming up from the magazine. If you put rounds in the chamber and then release the slide, you may eventually break the extractor.
BTW: to anyone that owns a CZ-75, be careful about loading rounds singly into the chamber instead of from the magazine.
The extractor is not beveled to snap over the rim of a round placed into the chamber manually, it is made to engage the rim of a round coming up from the magazine. If you put rounds in the chamber and then release the slide, you may eventually break the extractor.
