.00 Buck
I reload my own low recoil .00 buck shot 2.3/4 shells. I use 800X powder, Winchester 209 primers and a WAA12 wad clone and I usually reload federal top gun hulls. I buy them as field loads, reload them with .00 buckshot and stockpile for a rainy day. Then, rinse and repeat. In test after test of my reloaded ammo I am extremely happy with my pattern, shot column and minimal recoil and my cheap Mossberg Maverick 88 eats them like a fat kid eats cake.
Incidentally, I would recommend to anyone who enjoys shooting and likes to stockpile some ammo they learn to reload shotgun ammo. Forget the cost benefits they are not the real beauty of it. The real benefit is ammo quality control, customization, availability and self sufficiency.