When stored dry and cool, you will be fine.
The powder in the case may start degrade after a several decades though. Some of the old surplus WWII 30-06 ammo has produced a few duds and squibs in recent years. I read one report of at least a third of the rounds being bad.
Ammo that old is not common, and the surplus ammo can be of questionable storage history, which may have lead to the problem rounds.
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