My son has a 58 caliber SXS Pedersoli and it regulated well with round balls. I don't remember the exact load but he has taken several deer with it. The .50 and .54 are 1/24 twist and the .58 is .1/48 twist. I purchased a used Safari Express .72 cal rifle at the local pawn shop a few years ago. I had read that it regulates best with 120 grains of FF under a pure lead and a .715 ball so that's what I started with. It has a 1/75 twist and VERY shallow rifling. The .715 balls were VERY tight with .015 patching, almost needed a hammer to get them to start so I switched to very thin patch of pure cotton cloth. It loaded easily with these thinner patches. I was pleasantly surprised when it was grouping under 3 inches at 50 yards using the same rear sight off of a standing rest. My son could get it to group under 2 inches. I'm happy with it but it's a HOSS to carry at 12.55 pounds!
