Looking at my copy of the Gun Digest, "Blackpowder Loading Manual, Expanded 3rd Edition", the range of charges, using GOEX FFFG, was from 10 grains (1120 FPS MV/ 125 FP ME) up to 50 grains [Not Recommended, but safe to shoot in the Cherokee] (2016 FPS MV/ 406 FP ME).
They noted that 10 grain load enabled the owner to get 700 rounds per pound, again with GOEX. It is especially accurate with 20 grains, using a Hornady .310 RB & .010" patch. Both loads are great for small-game hunting at close ranges.
The 30 grain load is the "optimum" load (1871 FPS MV/ 350 FP ME) . The 50 grain load was not as accurate.
A 40 grain load (1919 FPS MV/368 FP ME) is ideal for turkey in states that allow rifle for taking such game at 20 to 50 yards.
The 24" Cherokee barrel has a 1:30" twist with .006" grooves.
"FPS MV" is "Feet Per Second Muzzle Velocity". "FP ME" is "Foot Pounds Muzzle Energy".
Hope this helps.
Buck