I think you are really asking 2 different questions. I do load work as rarely as possible as it is tedious and boring to me. I generally do it at 300 meters, as a club I belong to has a great electronic target system at that distance that makes it pretty painless. For 1000 yard competition loads I will try to verify the load at full distance before shooting a match with it if possible, but it doesn't always work out. Once I find a load I dont mess with it and i'll try to stick with it until it doesn't work anymore.
I do almost all of my practice at 10 meters.
I do almost all of my practice at 10 meters.