Did you try to reproduce the spent caps caught in the hammer??....You reported you found two....I found that very unteresting that somehting as simple as that would or could prevent the amount of spark making it down the flash channel. Granted I am new to this game of inlines - but not to percussion due to the amount of shotgunning I have done.

Dave....JW

I think those caught copper caps was enough to not allow a good seal on that nipple.