I never had to put 4f in the barrel to light off pyrodex. I was hoping to find a cleaner burning, noncorrosive substitute.
Black powder really isn't very corrosive. Black powder fouling is hygroscopic, but with a modicum of cleaning corrosion will never be an issue. Many 200+ year old flintlocks survive today with relatively good bores. I believe much of the black powder corrosion issues need to be blamed on the corrosive compounds used in the original percussion caps and primers for the early cartridge rifle that used black powder loads. The combination of the black powder fouling drawing moisture and the corrosive nature of the early percussion caps and primers made for a bad mixture that guaranteed barrel corrosion if one didn't keep them clean.
I've been using nothing but BP for many years in my muzzleloaders with no issues with corrosion. I keep my rifles clean but I'm not obsessive about it.
Mart
