My vote goes to K-frames and avoiding 125-grain bullets. 2nd place goes to the L-frame Mountain Gun, but that's too specific.
Yeah, the 125 grainers are likely the main culprit for shorter service life in K-Frames. They tend to really wear away the forcing cone. When they first agreed to make the K-Frame in .357 Magnum, what most cops were using were 158 gainers at lower velocities. Likely these are easier on forcing cones .
