With both inlines and my flintlocks I always sight in with a clean barrel...
I run 2 damp (both sides) alcohol patches down the bore, followed by a dry patch, a lightly oiled patch and another dry patch between each shot...
Now, once I am sighted in, I check to see what happens if I load with a dirty bore...Now, both of my flinters have Rayle barrels which have cut rifling, about .015 deep...Factory guns might be different...
In my .54, I can keep shooting by just changing from a .018 to a .015 patch...Groups go from an inch and a half at 50 yards to about 2 inches...So when deer hunting I just have a couple of balls in my loading block with the thinner patches and use them after the 1st shot...
My .40 is different...It needs to be swabbed with a damp patch between shots to group well enough for head shots on squirrels...