Quote:
Originally Posted by Ron Wood
To my understanding, guns are like alcohol, you can manufacture either (within limits for alcohol) for personal use without a license or federal involvement. If you are making it for sale, then BATFE rules must be followed. I do not believe there is a requirement to number a personal, functional weapon
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I can't point you to a specific thread, but Da Boyz at ARFCOM Build It Yourself are all about building up AR-15's from 80% machined receivers. If you have some time to spend, you can find the answer (from a BATFE guideline) somewhere on that Forum -
http://www.ar15.com/forums/forum.html?b=3&f=4
IIRC, BATFE strongly
recommends that you put some kind of number/identification on a home-built, so that if it is stolen/lost, ownership can be established.