G.T., What the heck, I'll add my 2¢ worth. I've had K-Frame model 19s and 66s. I consider SAAMI spec .357, of whatever weight, to be safe in these guns. That being said, I did see a K-Frame or two and a Python back in the day with damaged forcing cones. Caused by the ammo we used? I don't know.

We were issued 125 grain .357 for years, and I used mostly .357 recreationally in my model 66. My 66 never cracked the forcing cone, but developed excess end shake, timing issues, jacket/lead spitting, etc. I had S&W completely overhaul the old gun years ago. Were I wanting to shoot factory .357 that might be easier on the gun now days, I'd probably look into the 110 grain. It's my impression that major US manufacturers have loaded the 110 grain down to what might be considered a mid-range .357 load, around 1300 FPS. While I consider the K-frames safe, were I going to be shooting .357 extensively again, I would prefer an L-Frame, N-Frame, Ruger GP100 or similar...

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