Were these guns annealed before recase hardening? I have seen this several times on guns that I suspect that had not been annealed before they were colored. Your last gun was done by one who I knows does anneal guns. Was this part of the service? I like to have the person who does the case coloring reassemble the gun to make sure of the fit and that no warping has occured. Better to spend the extra few dollaors than to have to deal with the hassles that you are dealing with.