It’s all about the dates. Whenever a gunlaw is witten they almost always allow weapons imported, built, or registered prior to the enactment to remain legal. That’s why you can still legally buy fully automatic M16s and MP5s, if the lower receiver was registered prior to the Firearm Owners Protection Act of 1986 then any upper or furniture used with it is also a legal part of the full auto weapon. They’re typically pretty expensive, in and around the $10-15,000 range depending on age and quality but nothing says GTFO my porch like a full auto, belt-fed M60.
