This is actually insane. Simply..incredibly..insane.
http://newsbusters.org/blogs/ken-shepherd/2014/03/26/washtimess-miller-dc-judge-convicts-man-attempting-own-musket-balls
A Virginia businessman has been convicted of violating Washington, D.C. gun laws for possessing what amounts to, wait for it, replica musket balls. For that he was sentenced to time served, fined $50, and forced to enroll in the District's gun-offender registry.
http://newsbusters.org/blogs/ken-shepherd/2014/03/26/washtimess-miller-dc-judge-convicts-man-attempting-own-musket-balls