Their are a couple of ways of doing it. I also will do a couple of hundred or more set aside that has been sized primed and belled. If I'm doing just powder I will use a Sharpie and mark 10 rounds on the bottom fill the cases with powder. then do another ten with a different color Sharpie and charge with a different weight. Keep doing that for how many I want to test. the just seat and crimp the bullet and do all of the rounds. then arrange them in ammo box by the color Just make sure you wright down what the load is when you do it. I will put a mark on the paper with the Sharpie along with what the load is. I do two one paper goes to the range and one stays at home. just in case one blows away.