RE: old powder?
I have a can of Unique and Red Dot that were bought in the 70's .As long as the cans are sealed and in 50-80 degree storage a very long time . The corp I work for does that sort of storage I see TONS of both black and smokless new and recoveredthats over 30 years old every day . In fact I saw some 16" howidzerpowder charges just a year or so ago that were loaded in 1946 .