On the latest Dayz 1.05.152380, I put a pristine AR-15 fully loaded and chambered in to the military storage container (the smaller ones you can carry, not the big ones you walk into), then closed the container, then after a day or so (logged out/server reset) went back for it and the mag was missing from the pic (still visible below the pic) and the gun was still fully loaded, but then couldn't eject the mag.