Not to take sides,just putting my 2 cents worth in. When I test a double rifle,I always shoot on two targets,side by side. I shoot one with the right(or under)barrel and shoot the other with the left(or over)barrel, just as quickly as I can get on target. Then I put one target on the other and mark the holes. This is the only way I can tell of the gun is crossing or shooting wide. If I shoot,check point of impact,then shoot the second barrel;then I have waited too long between shots.When shooting more than once from each barrel, I let the barrels cool to ambient temp.between each set of shots. This may not be as important for a double as a cape gun,but I do it just to be consistent.
Mike
