Since the Democrats are entirely willing to violate white line Constitutional language, why limit it to the Second Amendment? Enforce with extremely severe penalties a complete media blackout on the name and sufficient biographical details of such shooters. The lack of a notoriety payoff will address quite a few.
Reverse or as so many are now saying ignore the judicial rulings that removed force as a tool in dealing with the mentally ill. [Redacted], and I think the above harsh and Un-American actions would all but eliminate the problem, and not for example, not that's it's going to be impossible, simply shift the tool of choice to the much more dangerous one of arson.