So, assuming I could buy a lower receiver through a private purchase...how would anyone ever know what I had?
Which, I guess, is the point?
If you sold it some day to some idiot that did something illegal with it. after he gets caught and spills his guts they will come to talk to you.
Actually, the idiot doesn’t even need to do anything illegal with the gun you sold him. If he does ANY crime involving ANY firearm, they will search and confiscate all that he owns and track down how he acquired each and every one. Just because there’s no paper or electronic record of a firearm coming from you doesn’t mean they would get the info out of him in some kind of interogation or plea.
You never know down the road years and years into the future how energetic the authorities will be in trying to track down every gun they confiscate and what kind of minor infractions they will or wont be willing to overlook.
Man this is the most mis-information I’ve ever seen on a thread in all my years on freerepublic! The best advise on this is to go to the AR15.com website and a simple search of gun laws for Texas on the web should tell you what you want to know. As for building the AR-15 up from scratch here is a web site that has detailed videos of all you’ll need to do and the tools you’ll need to complete it:
http://www.brownells.com/.aspx/lid=11004/guntechdetail/How_to_Build_An_AR-15_Video
I looked into this a while ago but living in CA makes it impossible so just gave up and will have to be satisfied plinking with my 10/22. Be warned that the cost of the tools may not make it worth the hassle and would recommend that you just buy a completed AR-15 from someone willing to sell it to you, much better bang for the buck that way.