To be clear, I did not experience this bug, but my mate did last night and he had to drop his drum magazine due to it not functioning properly. He logged various times in hopes of it working, but it did not.

The problem seemed to be that he couldn't interact with it as intended. One time, he dropped the magazine on the ground before he logged out and back in (to see if it fixed), and when he spawns back in he had the magazine back in his gun again. Although, it seemed to not be functioning again.

Tt was not going into his inventory properly, it was not coming out of his gun properly, he was unable to reload and switch mags properly.