The issue here is that "inherent inaccuracy" is undefined, so explaining it or measuring it is somewhat difficult. That said, I'm enjoying the discussion. So far, I see three possible definitions. 1 - the static geometric relationships among the muzzles and the line of aim. 2 - the static geometric relationships of the barrels and the aiming line. 3 - the dynamic relationship between aiming line and barrel line upon firing during barrel time.
It is clear to me that the dynamic result depends on the shooters physical reaction to the shot, as well as the design and construction of the barrels. Just as a handgun must be sighted in by the shooter to be truly sighted-in (rifles to a lesser extent), the shotgun would have to be custom regulated to the individual shooter to truly converge at a predetermined distance. Practical experience shows that this is a minor consideration in a very high percentage of cases.
So, Bushmaster, what is it you really want to know? Try some other words.
