I took a model 16 Smith 6" full lugged and had it rechambered to 32/20. Then I sent it to Simmons and had a new 32 Magnum cylinder installed. Now I have a K frame Smith that will fire either one (32 Mag, or 32/20).
First, if you do this, don't use a 32 Mag cylinder. It won't quite clean up in the neck area of the chamber. It does not hurt anything, but it would be better to use a 22 cylinder for this conversion.
I was able to get some pretty impressive ballistics out of that gun without hurting it any. The K frame Smith is pretty rugged for a 32 of any kind--even a 32/20.
Without going into the details, I was getting over 1400 fps with 100 Gr. Hornadys, and over 1600 fps with 71 gr. Remington bullets. I never tried the Hornady 60 grainer, god only knows what that bullet would do.
It was fun and interesting, but eventually I decided that a high velocity 32 was not all that usefull--I did not want to scope this gun, so I installed the 32 Mg. cylinder and let it go at that.