Colonel Peter Hawkers book,"Hawker on shooting," tenth edition , published and revised by his son in 1854, pages, 12&13 clearly describes choke and relief choke boring methods used at that time by British gun makers. Because concentration of shot at a distance had long been the goal of gunmakers/wildfowlers it is not surprising that simultaneous solutions to the problem were taking place both sides of the Atlantic if not world wide.

Roy Hebbes