That shimming thought had me thinking. Why not solder a thin piece of brass on one of the beveled sides of the front sight, then file it to fit? If you file the barrel's dovetail, then it's not a problem, but if you file the sight, then file the side that wasn't repaired. My first idea was why not make a new sight yourself, it isn't that hard, unless its sculptured. Another thought was to solder a piece of brass on the bottom, then gradually file the it to fit.But I rejected that idea because it will raise the bottom of the sight blade off the barrel.