Old Farmer brings up an interesting point.Choke boring is first recorded in Europe in the late 18th century. It was 1866 before the first patent related to choke was issued.[To the American gun maker Roper.A screw on muzzle adapter/shot concentrator, suitable for single barrel guns].The Roper concept was utilized by Tonks in America and Pape in the U.K.to bore double guns with choke present. By 1874 W.W.Greener had developed a method for machining choke constrictions in double guns that gave predictable paterns.This lead to a rapid increase in the manufacture of choke bored guns. In this era,the U.K. proof test of barrels utilized a solid ball sized to fit the proof diameter of the barrel under test. As a result,there must have been a rash of catastrophic failures on choke bored barrels at the Proof House.Hence the adoption of the,"Not for Ball," mark in 1875.Simultaneously the rules of proof were changed for choke bored barrel,with shot being substituted for a solid ball.
Over the past 40+years I have measured the bore of many English pre 1875 period guns, thus far I have never encountered any origional barrels that had any degree of choke present. I have found several unmarked barrels that had been back bored to create choke. In most cases these barrels were found to be out of proof 9 inches from the breech.
Last edited by Roy Hebbes; 04/14/11 05:05 PM.
