legality of (and BATFE stance on) NFA blueprints?

[Caimlas]

So, I was wandering around the Internet looking for the blueprints for various NFA firearms which hundreds of thousands of Allied troops used in World War II - specifically, the M3A1, and the Sten. I figured they'd both be readily available online, given the historical context.

However, I couldn't find any, at least not readily (well, I looked for about half an hour and found nothing, at least).

Are these illegal to possess or something, or are they treated like a hot potato? What's the deal? Are they treated like instructions for a nuclear device would be - ie, if you've got the instructions, you might as well be guilty?

 

[molonlabe]

Not prints but close.
http://www.liberatorcrew.com/M2-50/M2_Aircraft.htm

 

[AZ Jeff]

Blueprints for NFA weapons are NOT considered "illegal" to possess.

The reason you don't find them easily has more to do with who created the prints, and who "owns" the intellectual property for them.

Most US Military firearms, both present day and from most of the 20th century, have "technical data packages" which contain, among other things, the blueprints and specifications that describe the parts of any given military firearm. These packages are, for the most part, publicly available, but they need to be requested of the DOD, who is the caretaker of those packages.

Some firearms, such as the M4 carbine, among others, are proprietary to a specific manufacturer (such as Colt, in the case of the M4), and the tech. data packages are thus considered "company confidential" information.

 

[DoubleTapDrew]

I started getting catalogs from Delta Press <--- clickable (not sure why I get them, I think sportsmans guide likes to sell names) and they seem to have manuals for that type of stuff. On the pages with those types of manuals it says for informational purposes only...yadda yadda.
AFAIK it's no problem to have blueprints as long as you don't start trying to construct them without proper ATF approval.