@thendrix @EvilSandmich @Turdicus @Hoss @Moon The ammo suggestion does not work because of its poor density. Do you have any idea how large a room with 1,000,000 rounds of 5.56 needs to be?

Government agencies and other organizations stockpile ammo because it's feasible for them to own, maintain, and guard warehouses. But your apartment is not a warehouse.