Thunder, I was always told " If a Job is worth doing, it' s worth doing right" . Have your barrel drilled and tapped like Skeeter suggested.I' m not saying that the epoxy deal wouldn' t work but I wouldn' t use it or trust it on any of my guns.To me that would be a temporary fix.Any competent smith can easily drill and tap your barrel.It' s not very difficult if you have the proper equipment.Check your states regulations.Some states don' t allow scopes during Black Powder season.I hunt in Georgia and we' re not allowed scopes during primitive weapons season.I put fiber Optics on my Knight Disc and on my Old Renegade. It helped allot with my tired eyes. You might want to try this first before going through the expense of drilling and tapping ,plus the cost of the mount and scope.Just a suggestion.
Ruger Redhawk