I am thinking about purchsing a shotgun for birds, groundhog, squirrel, chipmunk, and othere small game and pests. What gauge would be best for me because I am not very big at all so I am concaerned about recoil. I dont need much nock-down power for just small birds so that is barely an issue. But I still want to be able to fire a tight pattern and kill a bird in one shot. I no next to nothing about shotguns so advice would be much appreciated.