Good question.
For me, I simply pick a known reliable powder that isn’t on the extremes of burn rate for the cartridge. That’s easy to select from the middle of the listings in the book. Known accurate powders would be options like H4350, Varget, N555, N565, N570, Retumbo, H1000, etc. they type of powders that are constantly used in the best loads from various cartridges.
Then, I’ll pick an acceptable velocity and powder charge. Depending on the cartridge, I’m often between 0.5 and 1.5gr less than max. However, it really depends on the cartridge. With mild cartridges like 6.5 creed or 308, I’ll often be closer to (but still well under) max. For magnums, I’m usually quite a bit lower than max.
Then I’ll pick the bullet I prefer for its BC, cost, reliability, and terminal performance. I’ll load that to whatever the typical is for that bullet. Perhaps 30 thou off for ELDX or ELDM, and 90 thou off for coppers.
I’ll select the primer based on book recommendation, but I tend to prefer Federal primers in most loads.
Generally, that’s gonna work. I’ll load up 25 so I have a couple sighters and then enough for a 20-shot group.
If the load meets my expectations, I’m done. If it doesn’t, I’ll make a major change like a different bullet.
For me, it’s about validating full recipes instead of running invalid tests with no statistical meaning until we convince ourselves with a single lucky 5-shot group that it’s good.
Others will disagree. We can still be friends, but I’m not sure if you’d still be invited to my birthday party lol 