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Your IMR 4895, any idea as to its age/date of manufacture? Could it have been some of the lots left over from World War II? You don't want to know the kinds of corners that were cut in production during World War II.
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No, neither did the seller. I picked it up at Camp Perry on Commercial Row.
The idea that gunpowder has a shelf life was news to the seller, I saw him last year and talked about it. Since he made a living selling surplus powders, it was not something he wanted to hear, probably thought I was part of the lunatic fringe.
After all, conventional wisdom is that gunpowder lasts forever.
I have more surplus IMR 4895, powder I bought before I was aware of all this, and I am shooting it up as fast as match schedules allow.
I am no longer buying old powder. No longer going to buy powder dating back before the 80's. I had about 16 pounds of surplus IMR 4895 go bad before, but I chalked it up to being poorly made powder. I had no idea of the underlining chemistry or that gunpowder had a lifetime.
Gunpowder is a high energy molecule and it will degrade to become a low energy molecule.
From
http://www.dtic.mil/dtic/tr/fulltext/u2/783499.pdf
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Nitrocellulose-base propellants are essentially unstable materials
that decompose on aging with the evolution of oxides of nitrogen. The
decomposition is autocatalytic and can lead to failure of the ammunition
or disastrous explosions. Many substances have been used to stabilize
nitrocellulose-base propellants,but by far the most widely used substance
is diphenylamine (DPA).
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If you are aware of the publication then you are aware that the military scraps ammunition when the master sample goes bad and the powder out in the field has less than 20% stabilizer left.
I had a link to a really good article at
www.dtic.mil and now it is busted. However, you can go there and search under insensitive munitions, stabilizer, and diphenylamine and find all sorts of information on gunpowders and aging.
This is a good article:
http://www.almc.army.mil/alog/issues...t_stab_eq.html
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Hatcher discusses this in his Notebook. He said after early National Matches where such ammo was fired it was not uncommon to find fired bullets with the neck of the cartridge case still attached. The pressures generated to force that combination through the bore must have been dramatic.
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Yes, cold welding was not well understood in 1921. The Army tin plated bullets and in time, the tin welded to the case neck. That was cause of all the pressure problems they were having with the tin can ammunition. In 1947, when Hatcher is writing his book, he totally misdirects the blame away from the Ordnance Department to greased bullets and civilians. Something that Col Townsend Whelen, who made that tin can ammunition, also did for the rest of his life.