For the first time since 1968, the Department of Justice's Bureau of Alcohol, Tobacco, Firearms, and Explosives is seeking to update the legal definition of a firearm to crack down on "ghost guns." 

The proposed rule seeks to redefine "frame or receiver" as well as classify more firearm kits as "complete" firearms, making them subject to more regulation and oversight. It also seeks to legally define terms such as "complete muffler or silencer device" as well as "privately made firearms." 

The proposed rule targets 3D gun printing.