That would all depend on what choke you are using, and what type of shot. For example, the turkey choke for my Benelli loves #6 shot for heavy shot, but likes #4 for lead.
To be honest, when I had my 712, I really didn't like the factory chokes (most factory chokes are not that great), so I bought replacement ones from Carlson's. They are nice enough, that you can call, and they will give you recommendations as to what might shoot well out of a given choke. Same thing for Pure Gold (makers of turkey and water foul chokes). Trulock's customer service is top notch, as well.
