I think bans work, but they need to be strictly enforced with a zero tolerance approach. There are plenty of examples of bans working well that pro-gun people like to gloss over or make excuses for. For example, Japan has banned handguns and virtually eliminated shooting deaths. They had 11 total homicides last year by gun. With a population of 130 million, that number is nothing short of astounding.
Pro-gun people will attack the nature of the ban and claim that Americans have more guns than Japan did before they enacted the ban, but that's not a valid excuse. If you made strict laws, over time, we could get down to a similar ownership rate.