The first SBH with 10-1/2" barrel was introduced in 1979 It had a tapered barrel with ramp sight, and the standard ejector. It won the first International Revolver Championship and finished turning the tide away from the Smith & Wesson Model 29. Shortly after Ruger introduced, in 1982, the .357 Maximum, Ruger introduced, in 1983, the KS411N, the first stainless Super Blackhack. The KS411N has an untapered 10-1/2" barrel, with stainless steel version of the Maximum ejector, and a screw-on target front sight.
Two prototype stainless Supers were built, one with standard 7-1/2" bbl, the other a stainless version of original 10-1/2" Super (tapered bbl, ramp sight, stainless standard ejector). The original "Silhouette Super," followed by the KS411N, rewrote the long range handgunning record book, piling on a staggering list of victories.
The KS411N was immediately followed by a blued version with the Maximum's aluminum, long ejector housing. (The Maximum has a hardened ejector rod.)
The original 10-1/2" Supers were made in Southport, and fitted with broach rifled barrels from George Wilson in Connecticut. A current 10-1/2" will have a barrel rifled on the hammer forge machine at the factory in Newport, NH. All Ruger single actions came from Southport until manufacturing there ceased in 1991. Tooling was trucked to Newport, where production resumed in 1992.
Without attempting to advise you whether or not to drill & tap the top strap of your Super, permit these observations:
* Given a strong base and rings, a properly D&T'd top strap provides secure scope mounting, while imposing no inertial stress on the barrel.
* A scope mounted on barrel increases muzzle heft.
* While a light, barrel mounted optic imposes little inertia on the barrel, a heavy optic amplifies recoil stress.
* if there is a clamp mount that holds zero and does not mar the barrel, I haven't used it.
David Bradshaw