Was cleaning out my grandfathers gun closer over xmas. He recently had to move into a nursing home. He has hundreds and hundreds of rounds that were stored inside the house in the closet. Probably close to 1000 30-06 rounds, about the same in 45s, 9mms and 380's. Lesser amounts of 30-30s, .222 and .270s but still around 300 or so of each of these. Im pretty much set for ammo for most of my life if they are going to stay safe to shoot over there years. Some of these are already 15 t0 20 years old but have always been stored inside and safe from any elements.
Thoughts on if they should be ok for awhile still?

I think about the only thing that would go wrong is powder deterioration. I believe that moisture present in the cases at the time of reliading is responsible for almost all cases of this, but i think it will usually show up as greenish corrosion on the bullet around the case mouth.

...or possibly around the primer...but RR's advice is spot on.

Old Mil Surp ammo usually has a sealer paint of some color around the primer to help prevent what you are concerned with.

You also could have found a lifetime career in breaking down all that old ammo. Hope it shoots well enpugh to use, and you can enjoy your grandfather's legacy gift to you.
Ron

Now you can hunt with Gramps for the rest of your life.

At least you have a surplus of brass to handload.

No offense to your Grandfather and I'm certain that he was a careful and exacting reloader. But I'm not putting anything in one of my rifles that I don't know the exact contents of. If you can find notes and records that confirm the loads it might be fine to shoot them. And it might be fine if you can't. Were the storage boxes labeled with the load recipes as they should have been? If it were me I'd take them down, discard the powder, and use the remaining components to reload more ammunition. Just saying .....

I have ammo that I loaded in the mid 60's,but I know what's what on it. I would take Creedmoor's advise on your GF ammo.

Luckily most all the reloads I have found have the date and info on what he did and used to reload the certain shell. Thanks for your advice. Ive never had any issues over the years shooting his reloads but just wanted to be careful going forward.

You Sir, are good to go!!

One thing I would make a habit of doing with that ammo.

You may or may not be using the rifle it was loaded for. I will assume you would sight in the rifle but I know I am bad about single loading when at the range .....I would function check the ammo before heading afield to make sure it works thru the specific magazine and actually chambers. I have seated bullets out for my specific long chambered rifle and they would not fit say a short magazine of a Sako or Browning rifle.
Chances are you will be fine but kind of embarrassing getting somewhere and having a single shot.

I can see both sides of it.

I personally have never shot someone else's hand loaded ammo and don't like the idea of it. On the other hand my brother and dad have been shooting my reloads for the past 15 years with no issues and they trust me.

I'd check them in your rifle if no problems arise I would fire them. Being they are old already I wouldn't make an effort to save them, shoot and shoot often.

good advice