I have some 8x57 brass and need 9.3x57. I have: New Hornaday 9.3x57 dies with the elliptical expander, CFL Case Forming Lubricant (Contains Amine Phosphate compounds), Hollywood Sr. press. In the past, to make 10.5x47R from 9x47R I fire formed the brass. This means several trips to the range, a 45min. drive one way. It worked well and I lost none of the brass. Still using it, in fact. I am using CH4D (Dave's) dies, with a standard expander, and was afraid of crushing the case.
Now, with the Hornaday expander, is it worth trying to do the whole thing on the press? No, I don't have a 9mm expander. My 9's are 9Mak's. I wouldn't anneal until the cases are expanded, I don't think. My brass is supposed to be once fired (yeah, I know).
I can always fire form them, I know how. I'm just curious if anyone else has used the Hornaday expander for sizing up?