I never have had a problem with running military 308 brass in a 358 sizer die. The only problem I've had with sizing to a different caliber is brittle brass. If your case necks split you will likely need to anneal. I've not had to yet with military brass. My dies have tapered expanders though.

I prefer classic.
Semper Fi
I used to run with the hare. Now I'm envious of the tortoise and I do my own stunts but rarely intentionally