Link? Last I checked anyone with reasonable mechanical knowledge and a bit of metal working skill could do it. May not be "caveman easy", but easy enough to someone who can read a simple set of diagrams. This simple set actually: http://www.scribd.com/doc/3853405/AR15-Lightning-Link-Plans
Or, in a pinch, be good with a freaking paperclip.
The ATF's standard is roughly that it treats a gun as a machine gun (legal definition) if it can be made to fire automatically with about the same effort as making an automatic weapon given a barrel.
Since it's fairly easy to make an automatic weapon given a barrel (the metal working isn't that difficult) ....
Yes, there are lots of "plans" circulating, but that doesn't prove that they work. Selling bogus plans is the perfect crime because the buyer can't complain.
FWIW, I've had a standing offer for years to anyone to demonstrate a conversion and have yet to have anyone even try. (I'll pay reasonable costs plus $5k AFTER the demo. Yes, you have to front your expenses - I'm not paying for failures or fraud.)
Sounds like entrapment tho buddy. I've personally seen a few conversions (in a different country, but same principles) so I know they exist and can be done. How do you convince any taker that the fact that they'll essentially be breaking the law to win your 5k won't land them in jail before they can even collect?
> I've personally seen a few conversions (in a different country, but same principles) so I know they exist and can be done.
I've no doubt that readily convertible guns exist. My point is that they're (and the relevant parts) are regulated as machine guns in the US.
The "principle" is that the receiver doesn't accept the parts or the parts, and possibly the receiver, are regulated as machine guns. For example, M-16 parts don't fit the semi-auto AR-15 receiver.
I have no idea how such guns and parts are regulated in other countries, but wouldn't be surprised if the laws were different elsewhere.
After all, some other countries treat silencers as good manners they're strictly controlled in the US. (Yes, I know about the plastic bottle trick. It's hard to ban duct tape and a plastic bottle, but it is a single shot device.)
Follow up WRT to the MAC-10, as that's the most prominent case where the ATF shut down production of open bolt versions for the "civilian" market (civilians can buy machine guns if made before 1986, there are about 100,000 of them in legal circulation).
What about by illegal means? I believe that is relatively easy. Theft? And, also, non-automatic weapons are pretty easy to come by.
Indeed a better way to put it would be that it is easy to obtain an automatic weapon with relatively little planning/effort.