Dang that had to be some recoil....btw speaking of recoil never leave the ramrod in your muzzle loader when you shoot it. No matter how cool it looks when Daniel Boone does it on TV it is not a good idea. Just trust me on this one. Also do not laugh at any friend that may do this or you may end up eating crow.
I admit that I know just enough to be dangerous.....but dangerous at ever extending distances.
It's to late now but I use Unique for lite loads and 296 for heavy loads. They are very accurate and they fill the case a double charge will run the case over. Sounds like your due for a RCBS powder checker die. Sorry for your loss of a fine handgun. At least you were not hurt,