Range pickup of brass.
Most cases are military brass — only a few have been found to not be.
On this last batch of brass, we have found some berdan primers in the mix, not very many but you don’t want to try to deprime them. They have a ring of green primer sealant on the bottom. Be sure to inspect your brass just to be sure.
This is about as much as you can fit into a large USPS flat rate box — best value