I never seen the OD military buckshot but I have seen Winchester buckshot that is VERY similar to the stuff you buy at Wal-Mart. Here's a few pics to shot what we use and what you can buy at Wally World:
What our ammo comes in:
The boxes and the ammo. Wal-Mart 00 Buck value pack on the left, USGI issue ammo and box on the right:
It works well enough but it's not going to have the tight Federal Flight Control patterns if that's what you're looking for. Like everything else, you have to pattern it in your own shotgun to see if it works for your particular gun.