Gnomon, are they going to be released or wild birds? I have hunted "buhds" most of my life down here. A 20 is fine, nothing bigger is needed even if the birds are wild. If wild, I would recommend a skeet and i/c. One reason is, this is your first go at it, and wild birds will get on out there pretty quick on you if you're not used to covey rises. If released, a cylinder and skeet, or two skeets. The released birds rarely get up and go like wild birds. Occasionally you will find released birds that came from captivity where they had long flight pens. They will fly much better.

Hope you enjoy it. Where are you going to be hunting, if you don't mind my asking?

Stan

May God bless America and those who defend her.