He jug choked them. As I remember he went back 8" to start the choke and continued forward 6". The last 2" in front of the muzzle were left alone. I read his book explaining it and it's what I've always done when jug choking a gun. First it was muzzle loaders in the 70's and now SxS's that use shells. It was a book I got years ago from a county library.