I have never chrono'd any of my guns mostly because I do not have a chrono.
I have always gone by group size. I shot a lot of offhand matches in my younger days and pretty much held my own. I shot some rest matches later in life and thought about getting one to help tweak my groups.
There are so many variables in loading, the whole process it makes really difficult.
Don't let me discourage you. There is alot to learn.