I surely don't know enough about sxs guns to argue with any of you gentlemen, but I will report my recent experience with a Spanish gun. It was made in the 70s, but still very tight when I bought it, like it had hardly been shot at all. The triggers were nearly 10 pounds, so that was likely part of the reason that it hadn't been used much, but the barrel regulation was just awful.

The left barrel shot way to the right and the right barrel shot way to the left. If you had shot at a stationary clay target at 30 yards, you wouldn't have touched it with either barrel. I can only imagine the frustration that shooters had with this gun trying to hit flying game. I bought it hoping to make a turkey gun of it, but thought that impossible after patterning. And it was consistent with every load I tried; left barrel shot to the right and right barrel to the left.

I didn't pay a lot for it and told my son in law that I was gonna leave it at our camp for a gun to shoot the occasional varmint; just remember which side to aim. Then a guy on another forum told me how to file the chokes to move the patterns. With nothing to lose, I decided to give it a try. I started removing metal on the outside of the left barrel to move the pattern back to center. It was only after removing about half the metal at the very end of the barrel that the pattern started to move, and then it moved quickly. I got it close to center for my field load, and then did the same with the right barrel.

When I tried my heavier turkey load, I found that the left barrel was perfect, but I had gone too far with the right barrel for the heavier load - it now shot to right. I had no idea if I could undo what I'd done, but gave it a try by doing a little filing on the inside edge. Just a few licks with the file and the right barrel was centered.

I killed a turkey with the gun this spring, and it centers well with both barrels. However, it will only center the heavy turkey loads. Lighter loads are still off a little, though much better than before. It was an interesting project.