tbh, the bigger driver of gun violence in the US these days isn't the prevalence of guns alone, it's laws around the use of them. For example, the 'stand your ground'-type laws which got so much press for the Trayvon Martin death demonstrably increased the gun death rate by heaps as soon as they were introduced.
EDIT: Peep dis.
http://www.motherjones.com/mojo/2012...trayvon-martin