<P> The Atomic Energy Act of 1954 was amended in 2005 and includes a provision (42 U.S.C. § 2201a) to allow Nuclear Regulatory Commission (NRC) licensees and authorized contractors to possess machine guns for the purpose of providing security . </P> <P> Importation of NFA firearms was banned by the 1968 Gun Control Act which implemented a "sporting" clause . Only firearms judged by ATF to have feasible sporting applications can be imported for civilian use . Licensed manufacturers of NFA firearms may still, with the proper paperwork, import foreign NFA firearms for research and development purposes, or for government use . </P> <P> The domestic manufacture of new machine guns that civilians could purchase was effectively banned by language in the Firearm Owners Protection Act of 1986 (also known as "McClure - Volkmer"). The language was added in an amendment from William J. Hughes and referred to as the Hughes Amendment . Machine guns legally registered prior to the date of enactment (i.e. May 1986) are still legal for possession by and transfer among civilians where permitted by state law . The static and relatively small number of transferable machine guns has caused their price to rise, often over $10,000, although transferable Mac - 10 and Mac - 11 submachine guns can still be purchased for around $5,500 . Machine guns manufactured after the FOPA's enactment can be sold only to law enforcement and government agencies, exported, or held as inventory or "dealer samples" by licensed manufacturers and dealers . Machine guns made after 1986 for law enforcement but not transferable to civilian registration are usually priced only a few hundred dollars more than their semi-automatic counterparts, whereas a pre-Hughes Amendment registered machine gun that can be legally transferred commands a huge premium . </P> <P> The Hughes Amendment affected only machine guns . All other NFA firearms are still legal for manufacture and registration by civilians under Form 1, and transfer of registration to civilians under Form 4 (though some states have their own laws governing which NFA firearms are legal to own there). Silencers and Short Barreled Rifles are generally the most popular NFA firearms among civilians, followed by Short Barrel Shotguns, Destructive Devices, and "Any Other Weapons". While most NFA firearms are bought from manufacturers and transferred to civilians through a dealer, many are made by the civilians themselves after filing a Form 1 and paying the $200 manufacturing tax . In some cases the manufacture is simple (i.e., using a pipe cutter to shorten a shotgun barrel), and sometimes quite complex . </P>

When were automatic guns banned in the us
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