Last month, a formal bump stock ban went into effect. The ban ordered anyone who lawfully purchased one of these devices to either surrender or destroy it, or else face felony prosecution.
Before the ban, the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) had recognized repeatedly that bump stocks are a lawful firearm accessory and are not machine guns, because a user of a bump stock still must engage the trigger once for every shot fired. In a 2013 letter to Congress, ATF explained that bump stocks “are not subject to the provisions of Federal firearms statutes” and “ATF does not have the authority to restrict their lawful possession, use, or transfer.