With a regular shotgun barrel. i am talking about a "bird shot" barrel with a bead site. If it didn't shoot to the point of aim I just bent it until it did. Usually it will improve your wing shooting as well.
When I was a tyke and dad was teaching me to wing shoot. i had a terrible problem with right to left shots but at the same time was KILLER on left to right. We would shoot and shoot ans shoot. even he noticed he couldn't "powder" clays but broke them better than I did. around that same time, I became old enough to carry my own gun for deer and dad liked me using the shot gun better than a rifle so my 20ga was it. We went to the range and found no matter the slug, the gun shot about 6" to the left. He stuck it in the crook of a tree and "bent" it. After doing this a dozen or so times he had me shooting right to the point of aim.
OBVIOUSLY you need to do this with care or you will kink the barrel ruining it.
Later on I speculated that bent barrel, was the reason for my inability to hit thrown clays we tried it and I (and he) was much better!!
Good luck,
CW