The question always seems to pop up on gun forums, including this one, about how long ammunition can be stored. Here is some .45 ACP ammunition that was manufactured in 1918. Not a single misfire.
I am currently shooting .308 from the 60's, military 30-06 from the 30's 40's and 50's and a bunch of paper hulled shotgun shells from various dates with no problems. But I know the ammo was always stored properly and I always assume that the primers are corrosive.
That said I have shot 5 year old stuff that was stored in a damp crawl space/garage that was junk
I fired some 8x56R Austrian that was WWI era...it went BANG when I asked it to but that straight pull bolt gun (Steyr Mannlicher M1895) was punishing to shoot.
I had some 45acp from WWII. It seems to have more recoil and power than Winchester white box ball Ammo. It even penetrated 15 layers of Kevlar, where white box would not.