The best-publicized one is probably the Firearms Act passed in Australia after the Port Arthur massacre. It restricts handguns and requires a reason to purchase them—target-shooting or some other rationale. They also have to go through training and use a borrowed gun at a gun club for six months prior to being issued their own firearm. They have to show continued active participation in a gun club to use the firearm. That is one approach. They banned semi-automatic weapons with large-capacity magazines, but they still have an active hunting culture, just as Canada does.
The U.K. went further. They banned handguns. They have an incidence of firearm homicides and admissions that's probably one-10th of ours. They took a different approach.
Ultimately, in public health, the solutions suggested need to be evidence-based, and those that are accepted need to be acceptable to the public. They have to be economically viable and feasible. They have to be legislative efforts the political parties can support, which is the exercise we're going through, right now.