Originally Posted By: 2-piper
IC choke on an English gun was generally around 0.006" constriction, even choke was only about 0.010" constriction. Since these are given as diameters only 0.003"-0.005" is removed from the actual wall thickness. "IF" there was ample wall thickness it would have been no big deal to have reamed the barrel a bit oversize leaving an IC choke at the muzzle.


Not much doubt in my mind it's had a hone job most likely to remove pits and they stayed away from the muzzle ends as to not make them too thin and just ended up with a whisper of choke.