Two of the most famous shootings in the country are the assassination attempt on Ronald Reagan and the assassination of Robert Kennedy. Both of those were done with .22 revolvers - a style of gun not even being considered by the anti-gunners. In addition, Gabby Giffords was shot with a hand gun. As a secret service agent said after the Reagan shooting, we can protect against ordinarily people but not against the crazies that are willing to die to kill someone. Notice that many of these recent mass shootings ended with the shooter killing himself or getting the cops to shoot him (suicide by cop is what it's called).