First, I'd outlaw the manufacture and importation of handguns. I'd include long guns which could be converted to a handgun. I wouldn't do anything about long guns.

Next, I'd confiscate handguns which came to the attention of authorities. I wouldn't look for them, but if a search turned up a handgun, it would go. If someone was carrying one in a car and the car was searched, it would go. Gradually handguns would become rarer and rarer.

Anyone with a handgun with a manufacture date after the law went into effect would go to jail for 5 years, no parole. The idea would be to get handguns out of circulation. After all, they kill 25 friends and family for every badguy, are counterproductive. Any weapon which killed 25 friendlies for every badguy would be banned.