I have given it thought; but concluded the practice could be viewed as overkill.
The only ammo I store is stuff like MilSurp, and I have opted to use GI-type sealed ammo cans for its storage. I have seen some very old MilSurp come out of such containers looking brand new, and there wasn't any desiccant involved.
The same is true of ComBloc MilSurp 7.62x54R packaged in their common Spamcan containers, no vacuum, no desiccant.
Greg