Denton,
Thank you for that LINK. It is extremely educational and I recommend it to all shooters and reloaders.
The idea that powder and ammunition will last indefinitely in a good storage environment is absolutely false.
Deterioration of powder, no matter how slow begins on day one. A takeaway from that link is that the experts consider all powder over about 20 years old to be suspect. Federal declares a safe shelf life of ten years for their ammunition. If one assumes that Federal is being very conservative and you double their shelf life figure you still wind up at 20 years.
According to the link the military keeps samples of the powder used in all their ammo and artillery shells and monitors it for years as to the rate of deterioration. When they estimate a lot of powder has three years of safe life left they put out a notice that the ammo with that powder has to be used up or destroyed by the three-year end date.
Extreme heat is shown to deteriorate powder very quickly. I wonder if this has been a problem for our military in the extreme heat of the Middle East?
I had heard that when the Marines or Army puts on a "mad minute" demonstration that much of the ammo used is old and needs be used up. I have heard this explanation when someone questioned whether the "mad minute" exercise was a big waste of taxpayer money.
Here is a civilian "mad minute" video. Multiply this effect several times over for some of the military demonstrations. These are used as morale boosters for the troops.
https://www.youtube.com/watch?v=KuSbT4T3o4g,
I am sure that I have some powder in my inventory that is at or over the 20-year point. I also have factory and reloaded cartridges that are that old or older. I will now make it a point to inspect and use up that old ammo and powder instead of thinking it will last forever.
Denton, thank you again for that educational link. I now know that it was nitric acid caused by deterioration of the powder that ruined my cases, even though the powder still looked normal. Given more time there would have been visible changes to the powder. As explained in the link, the problem is made worse by moisture or heat.
All the more reason to store ammo and powder in cool, dry conditions.
