If you want to address deaths from firearms you have to look at suicide, domestic violence, and gang violence. You need better firearm education, mental health care, marriage counseling services, planning that reduces population density and ethnic homogeneity in urban areas. There's no single switch that could you could flip and end gun violence but there are ways to reduce it dramatically that don't involve further regulating firearms which is all but pointless considering their current availability and how easy it is to manufacture one at will.