In 1996, 35 people were shot dead and 21 were seriously injured by a lone gunman in the tourist village of Port Arthur, Tasmania (Australia).
The response by both State and Federal Governments was to introduce some of the toughest gun control laws in the world. Gun crime fell significantly and has stayed low ever since.
Yes, criminals still get guns, yes, the odd "archival" firearm turns up in a crime, but overall, Australia is a safer place to live now because guns are tightly restricted to police, military, sports shooting clubs and limited rural applications.
The snivel libertarians will say, "Guns don't kill people, people kill people," but people with guns kill people more effectively than any other way and we're safer without them.