Sir Ron, Powder life is one of those topics that bring out the full range of opinions very quickly in gun forums. I find it logically and observably true that not only do, and or did, some powders have issues but heavy compression is an additive problem to powder life. Heat also is poison in the mixture. My one example is 65 grains of h414 in an ‘06 case turned solid in around 5 years. At least that is when I found it… I have an old 30-06 that used that much behind a Barnes 165 x to get up to speed. Very accurate and my father in law slew whitetail with it quite successfully. After he passed away I was going to shoot up the last of the ammo and had both a near squib and a full failure to fire. Pulled a bullets to find a solid mass of “melted” powder. Best regards F01
