The first step is to aneal the brass. This will soften the necks so they will resize with fewer problems. I make .25-06, 7 X 57 and 8 X 57 from .30-06/.270 family of cases. I have even played with taking .243 and 7mm-08 back up to the parent .308. Expanding progressively seems to make it easier. I can expand .277, 284, .308 and .323.
In life, strive to take the high road....It offers a better field of fire.
"Robo is right" Fuzzball