alsaqr, Hang fires normally do not come from the cap or primer. Usually from oil or dampness in the touch hole or the powder on the inside edge of the touch hole.The main exception to this would be trying to use #11 caps with a powder like 777 which I believe has the highest ignition tempture of the subs but they all have a higher ignition tempture than black that has to do with how they get classified ashazards material instead of explosiveas far as shipping purposes are concerned.Lee