I've been shooting a .313 neck Shehane for years. I use a 6.5 expander on Lapua brass and then a 7mm, I use a coated expander and Imperial sizing wax applied on the inside of the neck with a cotton bud, less force is good.
If you going to use a PMA cutter then get their expander to match the pilot they supply, the PMA tool is very good, again it's what I use.
I turn to 12.5 and use a .307 or .308 bushing and then use a expander, this gives me a loaded round of .309
Dies, I use Newlon blanks, ask who ever is doing the work if they have the resize reamer.
They are extremely accurate fire forming, one of the most accurate rifles I have ever seen was someone fire forming Shehane brass. I used to fire form using cheap PPU ammo and Trail boss powder, unfortunately now unavailable. If I'm just shooting into a back stop I jam them, if I'm using them for practice I sit the bullet where it wants to be. Run a mild load as you're not doing much to fire form the case just blowing the side walls out 10 thou, look for 2850 fps.