I have been using 385 grains of pioneer FFG. It is about 15% hotter than black powder but cleans up a lot easier. It is equivalent to approximately 440 grains of black powder. A fairly comfortable load as far as recoil goes. My chrony is on the blink and not working at the moment. I would say about 1300 ft/sec with the 3370 grain ball if memory serves me right. 12640 ft. lbs is plenty. It could be pushed hotter, but I don't enjoy getting beat up as much as I used to. Maybe I am getting smarter at 50. NAH!! I doubt it.