I have a Lyman Great Plains flintlock that is slowly nearing completion. I am purchasing items for shooting it one at a time now. I bought some ffffg the other night for priming but don't know if I should start with ffg or fffg. The literature that came with the gun said that either can be used.

Which one should I try first? I'm not concerned with maximum loads or high velocities, just concerned about getting accurate loads.