The bigger the buckshot, the more open the choke you need. OO should start with a Mod or Imp choke to test it...
I have killed an awful lot of deer and hogs for 45 years with it. Limit your shots to less than 50 yards and it will stone them if you center the pattern. If you don't, no firearm will help for a pulled shot. I would also advise you to go ahead and get COPPER PLATED buckshot. It will pattern much better than regular lead, esp at longer ranges. Good luck.
