I really like K frame .357's and will not part with my 66 no dash, BUT the K frame magnums had a weakness that cannot be ignored, which is why the L frame was born. Straight from S&W's mouth is "Only shoot 158 grain .357 in the K frame, and limit your use of those to familiarization and duty use". I have been told this on numerous occasions. Even Bill Jordan, the creator of the 19, advised light .357 use in the gun Now, some will chime in that their 19 has 10,000 125 grain rounds through it, but others will say their forcing cone cracked with only a few light mags through it. Since S&W does not make them anymore, and they only warranty guns made after 1989, if you crack a forcing cone, you're SOL. Why take the chance on a gun that can't be replaced? My 686 is a fine gun. Points differently than the K frame, but it's not different enough to disregard it. As a matter of fact, my 686 sits in the safe with a speedloader next to it, and is the gun my wife will grab if she ever needs one. The 66 is in a different safe unloaded, waiting for it's next day at the range, where it will shoot .38's, with the occasional 158 grain .357 thrown in for giggles.