Basically, to be fast, a flintlock must have the touch-hole slightly ABOVE the top of the level of the priming powder. This is so the intial flash of the powder ignition is able to touch the main charge on the other side of the touch-hole.This means the level of the priming charge needs to be about 1/16" below the touch-hole, and the hole itself has to have a short section through which the flash must pass to reach the main charge-very thin walls to the hole!

If the flame has to burn down to, then burn through powder in the hole, ignition becomes delayed.

In addition, when it is in the fired position, the tip of the flint should point down into the middle of the pan when the frizzen is open.

This shows where the touch-hole should be in relation to the powder pan.