ORIGINAL: sproulman
my measure is 36 years old,from thompson.it does not have screw on side to stop it half way.it goes from 50 up to 120 in 10 gr. stops but no screw to tighten.i most likely will use a marker to mark the halfway between say, 80 and 90 grs,unless someone has better idea.
FWIW, In my experienceyour muzzleloader rifle really won't noticea 5 grain difference...heck, on a 100grn charge there's almost a 5grn variance pouring one measure after another...and it's one of the reasons powder measures for large charges in rifles aremade in 10grn increments.
When you get down into the pistol size charges, those smaller charges use smaller powder measures and they aredesigned with 5grn increments, where a 5grn difference would be noticable when only throwing a 20-25grn charge in the first place.
Agood rule of thumb when starting to consider making any off the cuff modificatiosn to industry standards that have been proven for decades/scores/hundreds of years is to pause and rethink the situation...ie: there should really be no need to be making a 5grn black ink mark on a TC 50-120grn powder measure...if there was, the manufacturers would be making them that way.