browning sxs
i've never tested my skb as you describe. would just take it to skeet range and shoot 4 or 5 rounds of skeet prior to opening of grouse season and occasionally a round or two during season. i don't know what you hunt, if you're pass shooting ducks or geese you might be affected by the divergence of your center of pattern, but again when you consider that the error is 1 1/4 ins. at 10 yds., 2 1/2 at 20 yds. 3 3/4 at 30 and 5 at 40 from the left bbl-1,2,3,4 ins. at corresponding yardage from the right, this is miniscule compared to any error you may make in mounting or lead estimation when firing at game. if you are that concerned, i would fire from a rest to ensure the positioning was constant while testing. the amount of clothing you wear will have a significant effect on point of impact. here in ohio we have a 5 mo. season, oct. 10 to feb. 28. in mid dec. when i started wearing a heavier jacket i could notice a change. whether it was due to being a tad slower or mounting the gun differently i can't really say. i've always maintained that range estimation is the bugaboo in shotgunning. i,ve had my boys stand on the 40,50, 60, and 100 yd. lines after practice. you'd be amazed how far away they are. i don't know how any one can shoot a rifle and hit any thing at 300 or 400 yds. if you shoot that well you should be at vandalia shooting in the grand national. i'd take that gun to the trap and skeet range and see how i shot. if the birds don't break up to your abilities then i'd worry about the gun. heck, you'll have a lot more fun than shooting at an old piece of paper! sometimes we get caught up in trivia!