Not as simple as that. If that has been your experience, that's awesome.
Back in the wake of Sandy hook, needed 7-08, couldn't find any. Had ~5K of 7.62 and 308 assorted, so converted about 300, and wound up tossing ~ a dozen.
This was all for a AR10 Gasser.
I have found, some brass is thicker than others. For instance, most LC 7.62 will become 7mm08 with one pass, but ~10% of the necks will need turning. Some will never fit a case gauge no matter how much resizing or annealing you do.
Norma and Lapua in 308 are also slightly thicker, and a few cases (1 or 2 per hundred) will also need neck turning.