I shoot a .50 TC Hawken flintlock 15/16". I have 1 stock, 1 coned 1:48" TC 28" factory flint, 1 TC smoothbore converted from cap to flint using a Track Of The Wolf breechplug.
The original rifled TC with the original touch hole liner was prone to flash in the pan syndrome. The smoothbore, with a sharp flint, has always fired almost as quick as my cap Green mountain LRH (soon to be converted).
I swapped the touch hole liners in the flints and the flash in the pan followed the liner to the smoothbore so I measured the vents and opened the smaller to 5/64" and the problem was cured.
Now with a sharp flint both barrels seem to be the same and fire faster than I flinch.