Gentlemen: I used the Double Patched Ball load for years in Wyoming taking Elk and Bears. The rifle I used is a 50 cal. Lyman Great Plains Rifle and never hac any trouble at all. I also used 3f powder, both black powder and Triple Se7en. Load's from 80 grains to 120 grains dependent on size of animal and distance. Those loads at 100 yards in the barrel with 66 to one revolution of twist had two holes overlapping from a bench rest. I might throw one in 20 but not many if I paid attention to how I pulled the trigger and breathed. It all came to practice, practice, practice... The are very effective and most black powder rifles are safe with the barrel full of powder and one patched ball as the charge or most of it will just be pushed out the end of the rifle and not even burn up. Black powder just burns too slow. The Platt Valley Muzzle Loaders I belonged to in Casper Wyo. made tests on 9 different rifles the members had, with NO problems with any kind of damage. Just a thought. Pete