I have LC military 30-06 that I shoot mil bolt matches with, start with FL size trim deburr mouth and flash hole
anneal every 10th firing haven't trimmed again in over 50 reloads.
225/556 for the AR trimmed once, haven't trimmed again.
I got curious and measured some brass. A new never loaded Lapua 308 brass measured 2.008”, and the brass from MULTIPLE loadings measured from 2.010 to 2.030”.
I would more than likely need to trim if I was using them in a gun with a tight chamber, but my Blaser and TC Encore “custom shop” barrel are evidently pretty forgiving.