54??

[Gil Martin]

In my various .54 flintlocks I prefer 90 grains of FFG and a patched roundball. Sometimes I adjust the powder charge, but I like the sound of 90 grains. Everyone on the firing line stops shooting to see what just went off. Adam likes 75 grains of FFFG.

The local blackpowder gun shop owner swears by 60 grains of FFG or FFFG in .45, .50 and .54 caliber muzzleloaders. So it depends on what you prefer and shoots well in your rifle. All the best...
Gil