I was using RS (loose) in a .54 cal St. Louis Hawken during our Dec. muzzleloading season. After 3 days of hunting (and no, I didn't bring the gun into a warm house.....I took the cap off and kept it in the barn
) the gun failed to go off when I discharged it; it also failed on the second and third cap. On the fourth cap, it went "Fssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss ssssssssssssssssssssssssssssssssssssssssssssstttttttttt............................................. .................................................................................................... ..........................................BOOM!
A little unnerving, to say the least! I have sinced changed over to "real" black powder, and have yet to have a misfire in a hunting situation like that. Also, I found that with pyrodex, even if I didn't shoot the gun, it was still corrosive to the barrel.....black powder has been somewhat forgiving in that respect.
I now have two other muzzleloaders: a .44 cap-n-ball Remington 1858 and a .62 caliber trade musket. I would like to standardize on ONE powder, if at all possible, and since I can use FFFg in all, and get good accuracy with it in the Hawken, I think that is what I will be buying from now one (GOEX brand).