So, I received my model 686+ back from the S&W factory shop after having the barrel replaced. They ended up installing a complete rear sight assembly in the process of replacing the barrel, so the elevation needed some extreme adjustment when I got it back. The POI was about 12 inches high at just 15 yards. I began lowering the rear blade with the elevation adjustment screw, but it bottomed out before I could get the POI on target. Any ideas on what to do now?