I have two pinned barreled J frame S&W snubs 36 & 49. The 36 has the diamond grips the 49 is the standard , it looks like the grips are perfectly fitted to the frames , if I switched the grips you could see there slightly off . I would think the revolver frames are exact but switching the frames around there not . Looks like the older revolvers were given alot of attention , even to fit the grips to the frame. Installing oversized grips you wouldn't notice it , I wonder if the newer S&W are given the same attention?