I store my reloaded ammo in GI ammo cans and include small bags of desiccant in each one. Upon opening these cans, I've noticed an odor which smells like ether. I have not noticed this with factory ammo I've stored and it seems to be most noticeable with reloads using Dupont powders.
Some of my handloads are over 20 years old and they shoot as well as the day I loaded them both in terms of accuracy and reliability so performance doesn't seem to be an issue.
My question is, is the odor something to be concerned about?