Rem you really need to listen to the words of wisdom here. There is only one method of measure in this BP world, getting the right measure from the store is as just as important as the correct ball.
Going through all of this weighing and comparing is just opening yourself up for a problem, imo. And confusing the heck out of yourself.
Part of the fun is learning, and then doing it right, and expanding your knowledge of it. Just like you did when you were learning metallic.
The safest is the measured load, yup you will be able to eyeball it AFTER you get familiar. The Colt 45 case is a great suggestion....old one, and absolutely safe.....except for 777....forget that stuff until you want to chrony, and experiment.
Hope your first shots are safe, I am sure they will be,....after all , you are familiar with metallic loading, and know to be ultra conservative when working up a load.....hell use 3/4 of that 3.5cc dipper for the first shot,,....then you will see the "light"...ahem....Fire!!!
I love getting all greased up.... from BP.
Next thread for you will be how to clean it.....ROFLMAO.
Get out a bucket of hot soapy water......................