I have quite a few unopened Eastern Block sealed spam cans full of Berdan primed ammo which has a very long shelf life. I prefer storing powder and primers in a cool dry place in sealed containers, placed in larger sealed containers packed with desiccant. That way I have options about which types of cartridges that can be assembled as needed down the road. I worry a little about putting together far more cartridges than we would normally use in 5 or 10 years because the powder and primers will eventually deteriorate if not properly stored.
If Not Properly Stored..
Thanks