[Updated August 2019]
First, let's put all our cards on the table. We here at AR-15LowerReceivers.com may very well be purveyors of truth and dispensers of 2A liberty, but we aren't legal experts. So, before you take what you read here and run with it (especially if you live in California or New Jersey) you will want to check your local gun laws yourself. Make sure you are up to date on any applicable regulations, too.
Sadly, for every day that has passed since the publishing of this article, the gun grabbers have been working furiously to infringe. We do our best to update this article, but we can't always beat the politicians to the punch. Either way, you should find answers to most of your questions here. Let's get started:
What is an 80% Lower?
An 80% lower is a receiver blank, which isn't legally considered a firearm.
You, the firearm builder, must cut and drill certain portions of the receiver blank. This fabricates it to completion. Doing this turns it into a stripped lower receiver, a firearm by legal definition. Your finished, stripped receiver can then be used to build your own AR-15 at home.
How Does The ATF Define These Things?
You might have read this lil' bit of info on the ATF's website:
"80% receiver," "80% finished," "80% complete," "unfinished receiver" are all terms referring to an item that some may believe has not yet reached a stage of manufacture that meets the definition of firearm frame or receiver found in the Gun Control Act of 1968 (GCA). These are not statutory terms or terms ATF employs or endorses.
The term "80% lower" doesn't actually mean anything in the eyes of the law. It's just a label retailers came up with (and, realistically, they're about 80% complete). But if the ATF doesn't define or regulate these things, how do you know whether the 80% lower you buy is actually legal or not?
Simple, 80% lowers are just legally called receiver blanks.
What is a receiver blank?
Thankfully, the ATF does give us a nice, clear definition for receiver blanks:
"Receiver blanks that do not meet the definition of a "firearm" are not subject to regulation under the GCA. The ATF has long held that items such as receiver blanks, "castings" or "machined bodies" in which the fire-control cavity area is completely solid and un-machined have not reached the "stage of manufacture" which would result in the classification of a firearm per the GCA."
Basically, the ATF and the law separate an 80% lower from a stripped receiver (a firearm) based on whether the main cavity for the lower parts kit and trigger has been cut and drilled, partially or completely. They even gave us a nice visual comparison to show us what they consider a firearm, and what they consider a receiver blank:
Are 80% Lowers (Receiver Blanks) Legal?
As of August 2019, receiver blanks are legal to buy and own in most states, including California.
In Which States are 80% Lowers Illegal?
The only states restricting or directly banning the sale of 80% lowers are New Jersey and Washington state.
New Jersey A.G. Gurbir Grewal demanded retailers stop selling "ghost guns" to New Jersey residents. Even though receiver blanks aren't guns of any kind, Grewal specifically called them out. He also threatened any retailer who didn't comply with fines and legal action.
Washington state also recently passed legislation (House Bill 1739) banning the sale of "undetectable firearms". That means you can't legally buy, own, and build a polymer 80% lower if you live there. You can still purchase aluminum (forged or billet) lowers.
Are 80% Lowers Legal in New York?
While New York has tried to ban AR-15s and "assault weapons", they don't have any state laws restricting or banning 80% lowers or receiver blanks. Keep in mind that the New York SAFE Act does restrict how you can legally build your AR-15 with your finished receiver.
Like California, New York says your AR-15 must either have a fixed magazine, or be "featureless".
Do I Need an FFL to Buy an 80 Lower?
Since receiver blanks aren't considered firearms, they're not subject to the rules and regulations of the ATF.
Buying an 80% lower or receiver blank is legally no different than buying a roll of aluminum tin foil online.
Do I need a License to Build my Lower or AR-15?
Per the ATF: "A license is not required to make a firearm solely for personal use. However, a license is required to manufacture firearms for sale or distribution. The law prohibits a person from assembling a non - sporting semiautomatic rifle or shotgun from 10 or more imported parts, as well as firearms that cannot be detected by metal detectors or x - ray machines. In addition, the making of an NFA firearm requires a tax payment and advance approval by ATF."
Does my 80% Lower Need a Serial Number?
State by state, still mostly no. California builders will need to serialize their 80% lowers to remain legal.
Can I Sell an 80% Lower I Completed?
However, you cannot build an 80% lower with the intent of selling it. The ATF says that building a gun for sale or distribution makes you a manufacturer. Gun manufacturers are required to be licensed FFLs, which you are not.
But common sense says that our intentions change. If you finish a receiver blank and sell it later because you changed your mind about building a rifle, you're in the clear. But if you buy a bunch of receiver blanks, cut and drill them, and start selling them online as a "Bob's Discounted AR-15 Receivers" (which has happened before), the ATF will probably come knocking on your door with handcuffs in tow.
Use common sense here.
Are Receiver Blanks and AR-15 Kits Going to Be Banned?
You've probably heard rumors about this, so we felt it was important to clear things up.
Rumors exist, but there no active efforts currently being made to ban receiver blanks, 80% lowers, or gun-making kits. A federal bill (H. R. 7115) was introduced to Congress last year, in November.
The bill specifically calls for prohibiting "the sale, acquisition, distribution in commerce, or import into the United States of certain firearm receiver castings or blanks, assault weapon parts kits, and machinegun parts kits and the marketing or advertising of such castings or blanks and kits on any medium of electronic communications, to require homemade firearms to have serial numbers, and for other purposes."
Since being introduced, this bill has laid dormant with no calls for a vote."