been reloading about 30 years now and i have a question i don't know the answer to. a friend of mine gave me some powder he said was 25-30 years old.one is a 3# can of win. 296 0pened about 2# left the others are 1# cans all opened about 3/4 full. my question is the powder still good? the 1# cans still have that smell of new powder, the 3# can not as strong as new. any comments????