Might be related to issue, had this happen, and tried to eject the ammo from the 5 round mag, and the ammo disappeared.

works for me. check the content of the mag. they seem to be somewhat bugged so that they display rounds while in truth they are empty.

The magazine I loaded into the rifle was a new magazine that I found separate from the rifle. It already contained five rounds. I inserted the new pristine loaded mag into the rifle, the rifle loading animation worked correctly, but when I pulled the trigger nothing happened. I then removed the mag from the rifle and then emptied it and the 5 rounds disappeared. I can now no longer put other 7.62x39mm rounds back into the magazine.

Have had two magazines for this gun, didnt have this problem with any of them.

Same problem. CZ527 Magazine holds 5 7.62x39mm. You can load it in the CR527, but can't shoot. And also, when you eject ammo, you can't load it with 7.62x39mm.

yes had same Problem, in fact it is sks ammo.
The Mag Shows fully state, i emptied it, but no ammo came out, but still the mag Shows now 0/5. If i try to load the mag with the ammi he sais that it's the wrong ammo... So didn't work well.. Chamber the CZ527 works properly