Whatever gun that fits you and you can hit with. If you have any friends that shoot trap or sporting clays or skeet or whatever, hang around with them and try out their guns. If you can hit reasonably with a gun, then the gun probably fits you OK. Get that model gun suitably modified for HD. When I say suitably modified, I mean shorter barrel, a mag extension (maybe), a butt cuff for extra ammo, and maybe a light-that is all you will need, save the money for extra stuff and use it for ammo and training.