I just took my 25K rounds out of the .50 cal military ammo boxes they are stored in. I throw some desiccant in each box, then seal them the normal way. I opened them last week after three years in the garage. Each can I had to break the air seal with a screwdriver, you could hear the suction! The ammo was in prefect pristine condition. Each can holds between 3500-4000 rounds depending on size of brick or individua boxes! I love the .50 cal ammo boxes!