There were 2 full* magazines (7,62mm, 10 rounds, for Rahim) in the open crate at HQ and I could take an infinite amount of mags out of the crate, because the number wasn't decreased. Then someone else took those 2 mags and my "cheat" was not possible anymore.
-ca. 19:45 realtime (03.01.19)
-layout "Northwest" on Altis
*there were also half full mags, and the glitch didn't occur with them