If you are going to store ammo in metal containers be aware of possible condensation issues arising. What I do is put a couple of those moisture absorbing packs in with my ammo or cut a Odor Absorber in half (the ones for shoes) and include it. Anything with charcoal in it should also work.
An experience I had. I bought about 400rds of 7x57 reloads from a guy that his dad had loaded back in 1982 according to the load sticker on the boxes. The loads in cardboard boxes were OK for the most part (had to throw out about 30 as the box had got wet). The ones stored in plastic bags were in rougher shape. Dis-assambled about 200 of those. Bullets had rusted and cases had corroded. I saved about 150 of those. IMO just make sure you store them in a cool dry area, and not in cardboard boxes or plastic bags. When you decide to shoot them inspect them. If the cases are corroded, rusted etc., then I would be leery about shooting those. The structural integrity of the case may be compromised.