I have done some similar things in motorcycle shaft repairs as opposed to splitting cases and have had good luck with it.

The donor gun is a 4" heavy barrel, no adjustable sights. I'm considering machining for adjustables, I just haven't made my mind up yet. I might machine the barrel with Picatiny, or Bomar cut at the very rear (not sure if that would look attractive though).... DECISIONS DECISIONS!!!!

If I decide to go with stock adjustables, the barrel sleeve is definitely an excellent option!!

I'll let you know how the threads turn out, last revolver I barreled from a blank I had no problems with the threads on either half, but there is always that chance...