>>2852306Yeah, if you're good at cutting a consistent line on a ruler, you can do a burn rate test to compare powder pulled from old ammo to modern powders, but if you don't know what the rate was supposed to be or have good load data for the cartridge in question of the new powder, you might struggle to draw meaningful conclusions. And if you've got a reloading press and you're worried about old ammo, you can always pull it down and replace the powder with modern powder, generally for little money, the bullet and the primer usually are more expensive than the primer load, except in very high capacity cases. Surplus ammunition will generally get tested by anyone who sells it, though, and I've fired almost a thousand rounds of WWII era 6.5, over a thousand rounds of WWII era .30-06, ~800 rounds of WWII 7.62x54r, and some hundreds of rounds of .45 ACP, .30 M1 Carbine, and 7.62 Tokarev from ammo lots dating to the late 1940s and early 1950s. Well stored ammunition that isn't safe or isn't reliable in function is the exception, not the rule, even as it approaches a century in age. At least for the old style stuff, it's arguable that the less toxic priming formulations that have been in use for the last 50 years or so are less chemically stable, but they are also supposed to degrade into less energetic compounds, not more energetic compounds, so the likely failure mode is duds instead of detonations.
