Doesn't shot stay within the wad until it leaves the barrel and the only reason it separates once out of the barrel is the wad is lighter and loses momentum.
It makes sense that the polished barrel reduces friction, increasing muzzle velocity, and therefore the wad travels further with the shot before dropping off resulting in a tighter pattern. Has any one ever chronographed a before/after shot?
Do you polish with the choke installed so you don't mess up the barrel choke threads.?
Is it possible to polish to much, remove metal, to a point when switching to a different choke for upland bird hunting there is now a lip where the choke and barrel join up?