- Ban open and conceal carry. You can keep your previously purchased gun, but only in the privacy of your own house. Anyone spotted with a firearm outside is stopped, mighty fined and the weapon confiscated.
- concurrently edit a new license to carry a firearm, designed for hunters and sports shooters. After a test, they can carry their weapons in designated areas, at certain times for the hunters. Carrying a weapon from/to these locations has to be done safely (weapon disassembled, lock on the trigger, etc.)
- Ban the sale of firearms outside of strictly regulated dealers, which have to check the licenses and register every gun sold. No more gun shows, etc. A license doesn't allow for more than a couple of firearms. Losing one doesn't reset the counter, you can own a new one if you bring the old one back.
Once this is done, you can start regulating the ownership-at-home-without-a-license, by organising buyouts. After a while, when the outrage died out, you can pass laws regulating the storage of firearms at home, and allow for confiscation if the house is raided for another reason. Then tighten, and tighten again...
There. I solved your problem.