Yo, Tax! Sounds like a goodun! We'll have a shoot off someday with my CVA Mountain Rifle, also .54.
With BP you find the load that groups the best, not necessarily the heaviest powder charge. In fact, when you shoot over a clean surface like snow, you will see that a whole lot of unburned powder granules are wasted if you stoke her much more than about 80 grains. Those 120 grain loads just spill a lot of powder in mho.
And, yes, the hooked brass buttplates are their own version of hell on earth when it comes to felt recoil. That, and the crooked stock that dings your cheekbone at every shot!
o "The Earth is degenerating today. Bribery and corruption abound. Children no longer obey their parents, every man wants to write a book, and it is evident that the end of the world is fast approaching." Assyrian tablet, c. 2800 BC
o "In the beginning of a change, the patriot is a scarce man brave, hated, and scorned. When his cause succeeds, however, the timid join him, for then it costs nothing to be a patriot." Mark Twain
o "They have gun control in Cuba. They have universal health care in Cuba. So why do they want to come here?" Paul Harvey
o TODAY WE CARVE OUT OUR OWN OMENS! Leonidas, Thermopylae, 480 BC