Micro Red Dot mounting to .22 with RTV Silicone

I am considering mounting a Holosun 403R without the base to a .22, not the moving slide but nonmoving barrel with RTV Silicone. This would reduce weight and place the Red Dot lower than with the base and mounting rail. 

Has anyone tried this? did it work?  what did you think? 

Many Silicone RTVs achieve about 5 Mpa of sheer strength and this would seem like enough to keep it in place if sealed to the barrel or frame.

I tried something similar for mounting a Scatt or Mantis, attempting to attach a small rail with green Loctite 648 retaining compound. It worked pretty well for a week or two, but of course it did let go. Any kind of leverage from above will inevitably open a crack in the bond, and gun oils will finish it off.

Maybe JBWeld or something would work better, but is it worth it? You don't want it falling off, ever.

Loctite Black Max is the answer!  I use it for sight ramps, shotgun ribs, 1911 ejectors, and 1911 plunger tubes. No failures yet.

Thank you for the replies. The Locite looks interesting.