When I first started loading with my Lee equipment, I was using Hodgdon
Titegroup. That called for a light powder load in the 3+ grain area, for my
9mm. I soon found that this flake type powder, did not measure consistent for my 9mm.
If I didn't look at each load before seating, I would very often get a load
of only 1.8 or so, just enough to get a squib and lead stuck in the barrel.
Not a fun situation, especially for rapid fire which could be dangerous.
Since using Accurate #5 for most of my calibers, no problem when dropping a larger powder amount.
One particular load, I had to "modify" the disk hole slightly larger with a twist drill, to get spot on with what I wanted.