Yes, I've had that happen...seems when the fint edgewears down, shortening the flint's length, it hits lower on thefrizzen and to a point, seems to still work producing a lot of sparks...but then if it wears too short it'll hit so low that the frizzen might not even tip open.

After my range sessions andI'm cleaning everything up, if the flint looks like it's ready to be replaced, I don't throw them away...I just clean and toss them in a jar...the day may come when I'll run out of BEFs and try some used ones repositioned further forward in the jawsto see if I can get some more life out of them...an interesting hobby for sure.