You'll be just fine if you put them in an ammo can and store it under reasonable conditions.... fine for decades. However, I can understand that ensuring reasonable storage for decades could be an issue. So, if you seal them with a vacuum sealer and THEN put them in an ammo can, they should be good... pretty well forever. I guess I might put a desiccant pack in each bag.... but I can be a little OCD at times.
