I have a set of .38-55 rcbs cowboy dies. Neither expander is large enough to accommodate my 0.383 bullet.
I am a new lathe owner and am considering turning and threading a custom expander.
What steel is appropriate? A2 tool steel? Stainless? Should I flame heat treat it?
Edited I posted in gunsmithing as I am likely to find more lathe experience here than in the reloading equipment forum.