Shelf life depends mostly upon WHICH powder is used. And perhaps what primer formula for the older formulas.
I’ve fired lots (As in Lot number ####, AND ‘in significant quantities’) of military ammo 50 + years old that mostly functioned just as intended when it was manufactured. Maybe a few duds, but I’d bet that it was probably due to storage conditions that weren’t optimal, rather than just age.
Lately I’ve popped off some stuff I handloaded 27 years with commercial components that were a few years old even then.
Things loaded with 296 and Unique powders functioned just as they did back then... But interestingly, the ones loaded with Blue Dot powder GAINED in power... Enough to show some significant pressure problems.
But become unstable to the point that it goes off on its own? Only if you are storing it in the oven, and turn it on to broil.
....stuff I handloaded 27 years AGO with.....
Left out a word.
Doh!
THAT, and your whole post, is very interesting information, thanks. Hadn't heard that about Blue Dot before, but then, I'm not a real reloader. I've only just recently tried to assemble an inexpensive and easily portable kit I could use to hand reload in the field, if that ever became necessary. Unfortunately, purchasing powder and primers at the moment seems to be a real problem and everything is on hold.
Anyway, I wonder if Federal Premium is admitting they use such unstable powder and priming in their ammo? If so, I'll just make sure I shoot up all mine in the next ten years and not buy any more of it! I have a quite a bit, but not so much it'll be a problem sending all of it downrange over the next decade.
Blue Dot powder GAINED in power... Enough to show some significant pressure problems.
As a result load the Blue Dot using 88% of max. published loadings as MY “red-line”. It’s a Safety thing I figure. Gauge guns, rifles, and pistols don’t seem to mind.