Quote History Quoted:
A guy out of NH used to sell an 80% receiver tube for the Ruger (and others) but the BATF crushed him back in 2007 or so.
Just saw this link for various blueprints:
K.L.Stottlemyer & Co. View Quote
That was Kristi tool. He was in NH, but fled for someplace out west ( maybe Montana?). He was an honest guy, and a little odd; he refused to use the word "dollars" but instead called them "FRN" (federal reserve notes). You could also pay by "gold or silver bullion" (??).
All was well for a while. Then atf showed up with (iirc) some pissed off Canadian LEO "guests " - who of course had no authority in the USA at all (which is why they were "guests").
the best guess was that a few 80% recievers somehow ended up north, and they wanted KT shut down. Everyone knows the drill: they confiscate everything and hold it for an "investigation."
That tends to put small business out of business.
Anyway, the MK2 upper IS the serialized part - ie it IS the receiver. It's simple to copy, though I've never tried one.
Try here:
http://www.homegunsmith.com/cgi-bin/ib3/ikonboard.cgi