Believe it or not, I started hunting with flintlocks back in 1977 and have had one fail to fire in that time...I was squirrel hunting with my .40...I had shot several times and had stopped to clean and on the next shot I had a flash in the pan...Obviously, I had used too much spit and hadn't gotten the breech area fully dry...I dribbled a little FFFF Goex in the touch hole and she went off...

Same with my Knight, I always use FFF Goex and make sure my barrel and breech plug are dry from all oils and there is no grease plugging the touch hole...

The funny thing is, my buddies that started with percussion rifles never really mastered them, they got many more miss fires and hang fires than I ever have...They moved on to inlines and one who buys a box of Pyrodex pellets every 5-6 years or so still has hand fires...