Ralph T. Walker, "Shotgun Gunsmithing" stated that he deliberately tested roughing up the chokes, and the patterns diminished, then really smoothed them up and the patterns improved. His reply on the matter "those who think a rough choke improves patterns should go shoot some and learn." I rather think that the slits in polychoke types retards the wad better than just a rough bore. but then, the discussion goes round and round. As concerns pitting a bore, I say that is madness. Steve