There are a variety of effective ways to address this.
1. Purchase the guns in major cities, this has been done successfully in several places. Police departments have opened large stands and bought them directly off of the streets.
2. Obama needs to continue investing in border control, he has been good about this to date ( know your facts even if you don't like him ).
3. China has a limit to the amount of ammunition you can own and a variety of other effective measures that are serving them extremely well if you look at the data.
4. We have a TON of veterans here looking for work. Take the money we are wasting overseas and give them fucking law enforcement jobs here. They obviously don't need much training if any. This is my own idea. We are drastically low on cops in many areas. This kills 2 birds with one stone.
5. You don't need a fucking assault rifle to protect your home and family. If you do, you're going to lose that fight anyway. These should be completely off limits to civilians.