Americans owning full auto link...
http://www.autoweapons.com/pagelinks/buyandsell.html
Get a C+R license and pay class 3 tax and get approval from you local chief and you can own machine guns, silencers, cannons, tanks, ect.
Or we can play with the definition of automatic weapons and include hand cranked gatling type guns and mechanical triggers. All legal and kewl and fun.
In action..
http://www.youtube.com/watch?v=Gw970lgZjUo
Cabella’s gatling gun..
http://www.cabelas.com/p-0034775227757a.shtml
triggers
http://www.rapidfiretriggers.com/