Have you looked at the data from Hodgdon? They don't list that particular bullet, but they do list other bullets in 180, 200, and 220 grains with IMR 4064. Interestingly almost all the data for all those bullet weights starts at 40 grains of powder. If I was you, I'd start at 40 grains of IMR 4064 and work up to a max of 44 grains. Since I'm not you, use your best judgment.