Chuck H - I guess this barrel regulation stuff is harder for me to understand than I thought:
I am just trying to make sure I understand you when you say:" . . . 15-20% of the pattern diameter would be a limit." and then say "It doesn't matter what choke size we're talking about." Are you suggesting that pattern diameter doesn't change with choke size? Maybe I am just getting tripped up by symantics? Your point that large bore shotguns are more tolerant of poor barrel regulation than small bore guns certainly makes sense to me.
I know that choke size can be said to be the percentage of pellets within a 30" dimater circle at 40 yds, but it also seems to me that pattern diameter does change with choke size (see for example question no. 4 and associated table in this article by Layne Simpson
http://hunting.about.com/od/shotgun/l/aastshotgunfaqa.htm ).
Just from a seat-of-the-pants geometry perspective, it seems to me that choke size and barrel regulation deviation are related. For example, a shooter shooting a poorly regulated shotgun may still hit his target with either barrel with cylinder chokes but completely miss it with one or both barrels with full chokes (assuming same distance, same lead, same target speed, etc. Not that shooters normally shoot a SxS with both barrels having the same choke, but it illustrates the point, I think.). In other words, the larger diameter pattern of the cylinder chokes completely overwhelms any POI inconsistencies between barrels due to barrel regulation, where the same can not necessarily be said if shooting full chokes. The same affect would exists when shooting a gun choked Cyl and IC versus Mod and Full, the effect just wouldn't be as obvious.
Just wondering "out loud."
--shinbone
