I have visited with the Loctite technical folks about this project and they have concluded that no cyanoacrylate adhesive will long withstand the shear forces put on a glued shim. The nature of all "super glues" is they are very brittle. Loctite's effort to alleviate the problem was to introduce Black Max, which has micron sized rubber particles suspended in it. The techs were somewhat skeptical about its usefulness. I probably attempted half dozen shims with these adhesives. Only one has held and that gun sees very little use.

John McCain is my war hero.