If you extrapolate from FBI data, 90%+ of gun deaths come from handguns. Banning handguns is a hopeless endeavor - there are two Supreme Court cases from 2008 and 2010 that effectively cement handgun ownership as a constitutional right.

You could try a couple pages out of the California playbook with the handgun roster and ammo background checks to make getting them and using them kind of a pain in the ass.

I honestly don’t know what you do otherwise to make dent otherwise.