I see.  So, you believe the assault rifle is our biggest problem, eh?

https://www.quandl.com/data/FBI/WEAPONS11-US-Murders-by-Weapon-Type

Click on the buttons at the top of the graph.  Handguns by FAR outpace any other weapon in homicides.  You're nibbling at the crumbs when there's a whole loaf in front of you.

BTW, the problem isn't weapons.  The problem is our stupid jerks who are so willing to commit illegal acts and believe using them and violence to get their selfish, petty way is justifiable.  Take away guns, and they'll just bring them into the country illegally.  The problem is US.