Good advice.

Just be aware that if you start loading small-case, high-pressure calibers - like 9mm - the same principle doesn't always apply. Or at least not to the same degree.

In those calibers small variations in case volume due to different COL and bullet base shapes CAN make a significant difference, because the case volumes are so small to start with and the pressures are so much higher. In that case it is much more important to match bullet type and construction and COL to the published data as closely as possible.

And always start at the low end and work up. A chronometer is your friend, because although velocity isn't an exact measure of pressures, it is generally a good indicator, Without velocity info you're flying almost completely blind.