Playing on experimental early this morning 7 a.m. GMT or so. I witnessed this occur multiple times where the magazine would be picked up using keyboard, and since the inventory was full the magazine would go into the empty rifle/smg, but that rifle when equipped (from Alice pack) would appear graphically to be missing. Leaving/joining, nothing would fix the rifle or smg. Simply put if you dont want to bug out the gun and lose both it and a magazine (and ammo in it)., at this time hit tab to open inventory and make space. Some times auto equip on weapons when picked up onto weapons (even an EAST SILENCER replacements the improvised silencer in the alice pack).