IMR 4064 and Hodgdon Varget.
Mount the measure really solidly so it can't be jarred much, even by cutting grains. A heavy steel plate is nice.
That would be a huge improvement from where I was before. I had my powder measure secured to an end-table with two little c-clamps.
So, do the baffles for the hopper just keep some of the powder above a certain spot, therefor making your charges more consistent? I saw the drawings in your pdf file, just confused about exactly what purpose the baffles serve.