Re: 30-06 reloading ?
If you still have one of the factory loaded rounds pull the bullet and measure the brass, maybe you had some brass that was a little short from the factory, that way it may have grown but not enough to need trimming. I’m also curious when you say it did not need trimming, is that because it was under the SAAMI min trim to length or under the SAAMI max length? If the brass was shorter than the trim to length I would bet that your brass was short to begin with. If it simply is not yet at the SAAMI max length I say reload and shoot a couple it more times and then you will need to trim the brass.
I got the first shot and two reloading through my factory Federal brass before it reached the max length and needed to be trimmed.