Chiselian -
I knew the 2704 N. Central shop though never in it. They had a lot of shotguns on display. Later, with an interest in guns developing a model airplane club friend (and later a dentist) said the owner was under massive persecution by the city (Mayor Daley, Sr.). I passed the shop on Waukegan Rd. a few years ago but was never in it.
The Capone family had about five or seven brothers. One killed himself and another was killed in what may have been a police gun battle in Cicero. One went straight and may have becomne a local cop somewhere and was arrested in Florida on a minor shoplifting charge. I think he then changed his name. Another family member or two may have also done that. The Capone grave in a suburban Chicago cemetary had the headstone removed as it was being vandalized by families of past and relatively recent victims. The family is buiried in two cemetaries actually.
I had a Winchester 12 ga. model 11 (pump the barrel) shotgun which supposedly did time on guard duty in a Capone garage on the south side of Chicago 1927 and later. The guy I got it from was a credible source on the story.