According to Ruger, the 5.5" SS SBH, KS45N, weighs 45 oz, while the 5.5" SS RH, KRH-445, weighs 49 oz. My 6" half-lug 629, SKU 163606, weighs 45 oz. I like the 629 - as a big brother to my 629MG. I do have a 4.6" SS SBH, KS-458N, which weighs a bit less now than the Ruger advertised 45 oz due to the BHG I fitted to it. If you want a 45-49 oz gun, do as I did and go for a 6" h-l 629.
It isn't fair to compare the blued .45 Colt BH to a MG - they are 39 & 39.5 oz respectively - but the blued BH has an aluminum ejector shroud and gripframe, shedding a few oz their. Note that the same size SS BH's are heavier - with all SS parts. I think that the 629MG is a near perfect woods revolver - especially for the fellow who doesn't reload. The 629 MG is available again new, check your dealer. It will be a few bucks over the cost of the Redhawk. The 625 MG in .45 Colt is also available again - and, if you reload, it is a super firearm. I have both - and love them. The .500 Magnum style grips Hogue makes solely for S&W, and available for $35 from S&W Accessories, is a great recoil tamer, especially for that 629 MG.
Stainz