On a correctly regulated set of barrels we are talking about much less error than I can hold the gun to or even see when I shoot it. If the barrels had the same POI at 40 yards the math indicates there would be 0.43" (3/8") difference at 20 yards and the same at 60 yards.
This is for a 12 gauge. 0.730" plus 0.060" plus 0.060" equals 0.850 which give centerline to centerline of the barrels at the muzzle. Divide .850 by 2 to get the POIs half to 40 yards and half again past 40 yards.
Best,
Mike
Mike,
since the barrels converge at something like .010 per inch or more (don't quote me as I haven't checked in a while on a 12g), wouldn't the amount of POI difference, at other than the regulated distance, be based on the lateral displacement when the payload left the muzzle, from the muzzle from the sighting line (eyeball/bead) at trigger fall? The same would be true of the vertical plane as well?
