In my experience I have converted a .38 K frame to .357 then used it to test hot handloads and did so for many years without incident.


With that said, I purchased and used all the proper gunsmithing tools for the conversion, to include an action wrench, chamfering tools and a lathe which I already owned. I also took measuments, compared them to a new gun and carefully inspected all of the used parts (i did the same for new parts) and periodically reinspected everything. If you go this route and keep your loads below 1200fps your experience could be as safe as mine was. However, I used a new frame and used parts from de-milled guns which appeared to have been fired only a few times. I do not think that any of the parts that I used were from guns destroyed from shooting incidents.

Incidently I tested loads to around 1700fps whereas the frame did stretch slightly and the barrel had to be re-fitted more than once. I also shot loads to around 1400fps in a brand new Model 13 and over the years experienced slightly less frame stretching and top strap and forcing cone burn.

Good luck if you decide to give it a try.