Gun regulation in the US will always be an uphill legislative battle. Having guns is engraved within the foundation of the US Constitution, even common sense gun reform is a pain to pass. Gun reform works in many counties like japan, and europe but unlike those countries, guns in the United States are embedded and rooted within its culture.
If the goal is to reduce gun violence and mass shootings, instead of looking at it with a blunt solution to just ban guns, try looking at it with a more progressive position. Reducing the wage gap is one way, also political depolarization, and investing in infrastructure in general can have all sorts of long term positive benefits. reducing gun violence and mass shootings doesnt happen overnight,
Side Note: This comment is probably gunna get buried so i just say, one of my favorite presidents is Franklin Delano Roosevelt, yet one of the things i disagreed with him one was his idea of "Freedom from fear" which was a devilishly clever way of saying more Security, which was later used to justify gun regulation and is still apart of the Democratic platform today.