The charge can vary rifle to rifle, so that's irrelevant. What's important is what the chrono says.
I very much agree with this notion. Let the chrono dictate the load, not necessarily a manual or "internet load", although they are good indicators of where to start. A rifle/load will sometimes agree with expectations, sometimes not. I worked up five loads in the last two weeks that performed right on the money with regards to charge weights and velocities, which sort of surprised me. My odds are usually not that good.
I switched to a Magnetospeed unit recently and changed the way I do things. I'll just load the stepped-up charges about a half-grain apart and bang them through the rifle to find the appropriate velocity window, then I go home and load differing OAL batches for groups the next go-round. That way, I don't have too many overcharge rounds to pull bullets from. It's quick, as the Magnetospeed isn't difficult to set up. This works best when you are bringing multiple rifles to the range each trip.
