The original poster says Snopes verifies this story and does not offer a link.
Others say that this is an embellishment of the true story...and do not offer a link.
Annoyingly undocumented (no link, no validity, IMO) thread bump.
Thanks to DGray for the link!
doggoneit, I am getting careless in my old age and forget about the "surfing challenged" groups
http://www.snopes.com/crime/dumdum/gunshop.asp