When shooting percussion or flintlock, I just use a good measure with the funnel on top. I checked it against my powder scale and it was close enough to be in what it was supposed to be, with 3F black, that I'm satisfied. That scale is a Redding, oil dampened, from about 1959 that I've had since that time. I believe the total capacity is 325 grains. It still works just as good as when I bought it, but I do own a couple of jewelers scales that are digital and I use them for weighing the round balls I make. It didn't seem to me that my shooting with primitive weapons and open sights was going to be much affected by using the measure over what I weighed for the unmentionables through the years. I sure don't consider muzzleloader round balls capable of minute degree shooting accuracy, especially with hunting peeps sights. What few round balls I shoot at standing game is pretty minor compared, to what I did 25 years ago, with unmentionables, But it is fun to see just how good I am, or how poor I am, shooting at paper targets at different ranges with those round balls. Now it's entertainment, it used to be serious stuff.
Squint