Out of my 99, I settled on 40 grains of IMR 4895 and a 150 grain Speer Grand Slam bullet (old style) for 2625 FPS average. This is 1 grain below max according to my older book. It is a 1" load out of my gun.

I tried IMR 4064 as well as IMR 3031 and some Hodgen and Allient powders and a few other bullets (all 150 grain).