My side lock allways had trouble with any thing but good old black.
when I got a miss-fire I had an old sent bottle filled with 4f primer powder, I would puff a small amt thru the nipple and cap it then shoot it then clean it really well. Works nicely for those balls seated with no powder in the hole first, just tap the lock and blow 4f in the nipple till full. Makes a small pop and the ball pushes out just point it in a safe direction it still is a moving bullet. joe