I can imagine manuals are conservative, and there is strong basis for it.
Afterall, every barrel is a unique animal, and it really is best to exceed moderate loads with a questioning attitude. It's good learning if nothing else.
There are also those(like myself) who lean toward brass life over velocity.
I cull a little over a hundred for each thousand pieces of brass, before investing in preps & fireforming. That is, I rake 850-900 into a trash can -right up front.
I get the very best of the lot with this.
Then, I'm careful to find a 'moderate' load for the accuracy node desired. I really need those ~ 100pieces to last the life of the barrel!
Moderate is 50k-60Kpsi as validated through calibrated QuickLoad files. Go over 60Kpsi, and brass life shortens, no matter the SAAMI max listed for the cartridge, or lack of pressure signs in the short term.
This may be where you're at. And it could be completely fine for you, but still too expensive for me.
To find 'moderate' with your barrel/load, there is only one way I know to work:
I load 30 working up with new(but discarded) brass. Starting low pressure on up, I measure the case near the web(~.2" from casehead). Before long I will see the case grow to a point and stop(baseline), then as I keep going, I watch for .0005" (5/10thou) additional. This is the point of exceeding 60Kpsi(in my experience), and further increments begin to runaway with atleast a couple pressure signs, all the way to beating the bolt open and finding loose pockets. If you reach that with new brass, you've probably gone to 70-80Kpsi.
Anyway, MY MAX, is just prior to the .0005" jump in diameter over baseline.
So far, I've been able to hit good loads near that point, without exceeding it(I guess, because of the barrel lengths I choose per cartridge capacity). And with minimal sizing of this, occasional annealing, I have never wore out a single case in my life. This is why I'm so picky about the brass I'm gonna live with.
Just a different perspective on pressures accepted.