[Tom2]

If you see a milsurp green ammo can with the rubber seal in the lid, buy one, they are usually cheap, but don't settle for a junker. Some have paint, little bit of rust etc. on the outside, but should be pristine inside to keep. Good place to keep your ammo, protects against moisture, dust, etc. but not extreme temps if you store it in a hot place like an attic. Cold no problem. Some ammo will produce lower pressures on firing if very cold, but heat will deteriorate the chemical compounds in powder at some point. Leave it in a good ammo can with a good rubber seal and it ought to last as long as you need it. Maybe even last as long as your grandchildren need it. Otherwise on the closet shelf in your bedroom, probably will last about as long there, if left alone.