I can only mention that in my 4 Renegades, never go to the bigger ball. I purchased a mold to cast .530 and .535 ball. I learned quickly, even with a .015 patch that the .535 was way too tight. The ones I loaded I had to basically drive them down the barrel onto the powder with a mallet.. so I could shoot them off and then never tried again. But the .535 do shoot well in a Lyman, Cabela's Investarms .54 rifle.

I would go with the .530 ball and that .018 patch. It will load real snug and shoot just fine.