I've always felt that 4198 is a bit 'peaky' with pressures and that the volume per grain was not suitable, which is why I prefer the slower powders.

Concerning the loads - I used the load 75gr. ?4198 as being correct as that is the one listed with the target and the recorded velocity.

I should also say that I respect Ross for his experience and load testing and some other writers, few as those numbers are. I do wish Ross would stay away from writing about muzzleloading rifles though - there, his actual experience is a bit short.