Recovering Gun Store Commando. My Blog: The Clue Meter
“It doesn’t matter what the problem is, the solution is always for us to give the government more money and power, while we eat less meat.”
Glenn Reynolds
You could also try an advanced dive shop for SodaSorb or Sofnolime buckets. They come in the 5 gallon variety most of the time. Since humidity and flooding don't seem to be an issue, seems the 5 gal is the way to go.
After outgrowing the gallon zip loc bags, I had planned on switching to 5 gallon buckets. But I found them to be a bit too big for the amount of brass that I have.
I ended up getting a few 15qt Hefty plastic storage bins and they work for me. They have locking lids, stack nicely, and for some reason my wife doesn't mind them in the closet, whereas she was not excited about having 5-gallon buckets in there. I may get some smaller ones for the calibers that I shoot less.
I store mine in an airtight pet food container.
They go up in size to about 66 qt.
They also have another type with screw on lids that are stackable.
Ps the wheels won't make it under the weight.
I use 5 gallon buckets as well.