The idea is something I talked about a couple of years ago when I built my AR from an 80% lower. In every legal sense, this is an AR-15 rifle:
Advanced Rifles offers a very reasonable conclusion here. Let's say you own a Bushmaster model that has just been made illegal by your state. You are required to turn it in or register it. If you remove the lower receiver, remove the trigger and all the components in there, stripping it down to just the hunk of metal and a pile of parts, that stripped receiver you're left with is the Bushmaster AR-15 in every legal sense. You can hand in that stripped lower receiver and comply with the law.
Now what? You have an upper receiver, barrel, chamber, bolt, charging handle, stock, buffer tube, trigger kit, all the things that are legally just parts made of metal or plastic. All you need is a lower receiver. You can now buy an 80% lower receiver, complete the machining yourself, and rebuild those parts you previously removed into/onto your new rifle. But your lower will not be any of the rifles banned by name anymore because it's not the Bushmaster you started out with. It may have a Bushmaster upper with a Bushmaster stock and a Bushmaster lower parts kit but it will not legally be a Bushmaster. It will be whatever you decide to call it. (Mine's a "Mo's Guns")
I, of course, have had links to how I made my AR up since I started the job. Unlike me, Advanced Rifles promises to stand behind you and help you build your AR. It can be done with a milling machine (if you have one, you probably don't need me to tell you this) or a drill press. Advanced Rifles likes to call it "monkey simple". You don't need to hold outrageous accuracies to complete an AR. Remember the AR made out of HDPE - essentially a kitchen cutting board? Let that be your inspiration. I should point out that as of tonight, April 17, 2013, Advanced Rifles is getting quite a bit more for their 80% lowers than Colfax Tactical, where I got mine. The Colfax Tactical non-anodized lower is $99, with $10 more for anodizing. Advanced Rifles is getting $180 for their equivalent, non-anodized lower. Advanced Rifles seems to be offering more in the way of an online community and support to help you through the build.
Edit 4/18 2100 EDT: I had a nice email from Advanced Rifles about this post. Due to the very high response they've had, they've been able to get some higher quantity discounts and lower their prices. They also think they'll do better on order backlog time than Colfax. I'll quote a few pieces here:
Your observation on pricing was accurate and we have been in the middle of revisions for the past week. We did not expect the response from the market and the patriot community that we received. "THANK YOU!" is the only thing we can say! We have been able to make changes that can only come with high demand. We were able to bring in more staff, acquire larger/faster equipment and do larger bulk purchases. The boost will dramatically lower costs over a longer period of time. Which we are passing all that savings back to the community. We will still be able to continue our support of the community in other ways at this volume and price point as well. This is going to be fun.So count me as a fan of Advanced Rifles. They've got a nice handful of innovative ideas there - American small business at its best.
$120-ea / $110-5pc
There is still a spread, but not much. We will need to get more than Colfax / Redmond due to to the broaching of the mag well. It costs more to produce that way, so it needs to get bundled into the sale price. However, our capacity means that once we get through this catch up period, we won't have a backorder problem. The other guys are 6-12 months out on back orders.
No financial ties, no affiliations, I haven't bought a thing from them, I'm just an interested observer on this. My next project is either going to be an AR from aluminum plate or it's going to be a 0% lower.