When forming 9.3x57's from .30/06, I had to turn the case necks. If you have a sloppy chamber, this might not be necessary. My 9.3 has a very tight neck, the body is oversize in length is all - which of course, is excessive headspace. Opening up the necks fist will eliminate the headspace problem of merely necking up 8x57, and also eliminate having to trim to length and possibly neck turn or inside neck ream.