Here is what the late Tom Ball told me back in 1999 when I asked for sighting help on a Pietta remington that I wanted to bring to POA @ 30 ft.:
": Hi, unscrew your barrel a little bit, if you put a scribe mark on the barrel and frame, unscrew it about the width of the scribe. Which should move you about an inch and a half, then you may need to unscrew it a bit more! Until you get it where you want it. Remove the loading lever assembly, and cyl pin and put a witness mark between the barrel and frame whereit enters. Put the barrel in a vice, with thin [cereal box thickness] on each side of the barrel and tighten up! Then use a big adjustable wrench, with cardboard between the jaws, and clamp firmly on the flats of the frame just behind the barrel, and unscrew it a little bit which will move the front sight to the right and cause the shots to go farther left! that is unless the gun is a Uberti, then the barrel is locktited in and cannot be moved. "
Since then I have read that you can heat the frame of the Uberti and soften the epoxy but who needs to when the Uberti front sight can be tapped over in its dovetail.