I have the Nz-85b, along with 3 magazines. Two of them gave no problems, but the third....

. It seems down in the bottom of the mag where the hole is punched (rather ragged) is where my problem was.
I took my mag apart, and carefully took the rough edges off the protruding (to the inside) bump. A little smoothing on the sides and a bit to the top. When the mag spring gets compressed, the bottom of the follower bottoms out on this bump.
The spring can sort of bind on the rough edges as well. Go about it slowly, as a fugg up could turn it into a prohib mag. Just take your time, and you should have no more problems, if this is indeed your problem.
Maybe hawk223 can explain it more clearly than myself. Also, was looking for springs on Wolff site, and I think there's a mention that the CZ ejector/extractor?? spring was the weak leak. Good luck. Mine shoots well even with me behind it!
