My 500 Linebaugh by Hamilton Bowen is built on a Redhawk frame with custom micarta grips. My .45 Colts come in Ruger Blackhawk SS Bisley 5.5 inch, Clement converted blue Redhawk 5.5 inch with minimum chamber dimensions and a plain stainless steel Redhawk 5.5 inch. My lightweight models include two S&W N frames: 6 inch Model 25 and 4 inch mountain gun 625. I say build a 500 Linebaugh on any frame you like by any of the gunsmiths listed here. A lighter frame gun requires some restrictions in loads. A Blackhawk or Redhawk in a big bore caliber has reasonable end weight and very little load restrictions, due to cylinder length with a lengthened frame window and an oversize five shot cylinder. A Super Redhawk in 480 Ruger, chopped to 5.5 inches will pretty well do all that's needed and cost a lot less than a custom revolver, in a nice middle of the road big bore package. The 7.5 inch might be short enough to leave as is. There will be lots of sneers I'm sure but the Taurus Raging Bull 480 Ruger 6.5 inch is not really that bad as it is. Weight is a bit heavy at 3.5 lbs but still packable in a shoulder holster. Around 3 lbs seems to be enough weight in a belt gun in my opinion.