OP - an example of "working up" a loading. I have a new-to-me 22-250 rifle. New W-W brass. Fed 210M primers. Speer #1035 52 grain Hollow Point "Varmint". A correspondent advises real good luck with IMR 3031 powder, and I have some on hand. Speer manual lists 32.0 grains as Minimum and 36.0 grains as Maximum, using Remington cases and CCI 200 primers for this powder. So my intention is to load 2 each and do a pressure series - 32.0, 33.0, 34.0, 34.5, 35.0, 35.5, 36.0 and 36.5 grains. So 16 rounds. Could be fired off into a ditch - not too concerned at this point about most accurate loading - I want to find where is Max, in my stuff, if it is there. If my bolt is going to "freeze up" or worse, I want to "feel" that coming with lesser loadings. There might be a more "scientific" way to find the most accurate loading - I will likely back off 0.5 grain from any pressure signs (if I get some?) and try 5 round or 10 rounds groups. Once I find something "good enough", that will likely be my loading to use. No doubt at some point I will use the MagnetoSpeed to get a velocity reading or three - to see. I am not terribly interested in wringing out the last fps from this rifle and bullet. But I do want it to be able to hit a crow in a tree or in a pasture - at 200 yards - like my last 22-250 could.
For this start, I will likely use the COAL length as given for this bullet by Speer - 2.350", after I confirm that does give me some amount of "jump" in this chamber - most manuals, I think, show you how to do that. Afterwards, if the magazine allows - I might play with more or less "jump" to see if that makes a difference on the groups that I shoot. The rifle's receiver recoil lug has been epoxy bedded, and the barrel is free floating - I have received a Leupold 6-18x40 scope to install, yet.
I also note that the Sierra V manual lists IMR 3031 with their 52 grain HPBT MatchKing bullets - using Federal cases and Fed 210M primers - they Start at 30.1 grains and go to 32.9 grains. Neither Hornady 9th nor Nosler 9th list IMR 3031 powder with their 52 grain bullets. To be seen what I get with this rifle and my components. I am pretty much convinced that loading manuals are reports what they got with their guns and their components, when they ran them on their pressure testing machines. I do not have any of that - I don't have a pressure testing machine, and they did not use my rifle or my components, so is not likely the results would be identical.