wow pretty interesting is that a homemade conversion?? or is that something TC is doing now?? a small pistol primer in my opinion would be great ignition for a BP rifle, I use the 209 ignition but seems to hot for BP. somewhere I read the cci 209 primers are on the less hot side of primers so thats what i use now seems to work good. but a pistol primer would deffinately fill the gap between a musket cap and a 209 primer.