I've only used it in .45 Colt cartridges shot out of a conversion cylinder in my Old Army.
I used 22.2 gr. of BH 209 pushing a cast 255 grain flat point bullet. That's the maximum load recommended by BlackHorn.
Accuracy was so-so at 35 yards about a 6-7" group for 6 shots. I may decrease the powder and see if that's more accurate .. after hunting season.
I've got a set of nipple conversions promised for the ROA that will fire small pistol primers. If they are hot enough to ignite BlackHorn reliably, I'm going to have a new favorite gun and load for hunting. I can't wait to see if they will do the trick. :face: