Trail boss.
Trail boss is great, I stumbled on this thread seeking data on B.P. .45lc loads, so far I have only used trail boss behind 250, 230, and 200gr lead I think you will be safe, working up untill you see signs of pressure, or you find the muzzle flip a bit much for shooting holes in paper without a actual grizzly bear charging you, as I did. 5.7 gr was more than needed I felt, and started back at 5.5 and stayed there. Good luck.