I've a CVA hawken with both .50 and .54 barrels.
the 1-70 i _think_ is a true roundball twist, conicals needs a little more twist to stabilise, or thats what i have been told.
My .50 bbl likes 85grains of ffg pyrodex tight load, but my .54 likes 90grains ffg pyrodex loose loaded.
YMMV, just see what she likes and go with it, from the looks of that pic, i think you found what she likes
