Quote from the article:
Try the 12 gauge loaded with some old fashion 00 buck.
Better not get caught hunting ANYTHING with buckshot in Oklahoma.....it's VERY much illegal......BB shot is the biggest legal shot size for anything other than waterfowl and crane!
From the Oklahoma Dept of Wildlife website:
Shotgun Pellet Size
No person in the field may possess or attempt to harvest any wildlife, except waterfowl and crane, with a shotgun using shot larger than conventional BB (.180 in. dia.).
Couldn't find it online and I don't have a copy of the waterfowl regs here, but I believe waterfowl and crane hunters can use shot up to "T" size.