Thread: Old Ammo Affecting Rifle Accuracy?

Please excuse the ignorance of this question but it is possible that using old Ammo can affect the accuracy of your Rifle?

I've have quite a few boxes of at least 30-year Winchester 308 Ammo, and for cost reasons usually use it. However, I recently tried some new Winchester 308 Ammo (same Bullet Head, Grain etc. as the old stuff) and the new stuff shot a way closer group with my most 'finicky' rifle (a Rem Model 7, with its thin barrel and all).

So, can old Ammo through simple deterioration over time in fact affect accuracy?

I'm not a hand loader, so don't fully understand gunpowder theories etc.

Thanks