Rocky Mountain Arms made a 22 cal breech loading black powder rifle. The breech was rotated open and powder and a ball inserted, when the breech was closed a toy cap was used under the hammer to ignite the powder. Nice little rifle you have there.I think I saw one of these a long time ago .. I would like to see how the cap sets off the charge. Im sure one of these would be hard to find ,but like others say it can always be duplicated.Thanks for showing it !