There where a couple of posts about full auto machine guns. I am not going to go back and find them just so I can quote the original author. I am also not going to debate if you should own a machine gun. I just find that there are a lot of misconceptions about full auto firearms.
Here is the straight skinny on legal machine gun ownership...
Before 1934, you could freely buy, sell, and own full auto machine guns. You could go down to your local Sears and buy a Thompson sub-machine gun over the counter with no questions asked.
After 1934, you could still freely buy, sell, and own full auto machine guns, but you had to register them and pay a $200 "transfer tax" anytime the firearm changed ownership. The registration paperwork would also have to be updated to reflect the new owner. If you owned a full auto firearm before 1934, it too would have to be registered.
In 1986, the government banned the manufacture of all full auto firearms made for anyone other than military and law enforcement.
Machine guns made before 1986 where grandfathered in and as long as they stay registered, they may still be bought, sold, and owned by anyone who would be qualified to own any other firearm. i.e. not a felon, not wanted by the law, not deemed insane, etc,. Because there where no more machine guns made for civilians after 1986, guns made before 1986 have become rare and very valuable. A pre-1986 AR-15 can run you well into 5 figures.
Laws are different from state to state but for the most part, machine gun ownership is still legal. It is however usually cost prohibitive.
This is a bit over simplified, but I think I hit the high points.
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