I've owned a Whitworth rifle, and a .451cal Volunteer rifle since the early Eighties, and the Musketoon since the late 70's. I know what a Volunteer rifle is. I have a Pritchett Volunteer rifle as well.The Whitworth has a hexagonal bore. The Volunteer has "normal" rifling, perhaps Alexander Henry style. All are good, but a Volunteer is NOT a Whitworth.