Does gun powder have a shelf life? I inherited a good bit of powder. Can anyone advise on the effects of age on powder and primers. Will it "go bad" with age. Powder came from the dry region of California. Kept dry. I do not know how old the powder is, however, there is one can of "alcan" powder. Powder cans have been opened as he loaded several different calibers. I also received several thousand primers of the same age. I am thinking like 30+ years. There was also some loaded 45 rounds of the same collection. They do go bang, without any problems. Any info would be appreciated.