Here are some 5-shot velocity averages I got over the chronograph with my Mustang and 385 grain Hornady Great Plains bullets. All loads were 90 grain volume.

Triple 7 FFFG - 1583 fps
Pyrodex RS - 1144 fps
Jim Shockey Gold FFG - 1018 fps

However, the JSG gave me the tightest 100 yard group with that load.