80% lowers such as 80% AR-15 Lower Receivers are items that have not yet reached a stage of manufacture to be considered a firearm.
The term “80%” is actually just industry slang and not something endorsed/used by the ATF (Bureau of Alcohol, Tobacco, & Firearms).
We’ll cover some common FAQ’s, other examples of 80% lowers besides AR-15’s, and recommended manufacturers.
Disclaimer: I am not a lawyer and this is not legal advice. Be sure to check all your local, state, and federal laws.
Table of Contents
Are 80% lower receivers legal?
They are legal to own since they do not meet the definition of a firearm under the Gun Control Act of 1968 (GCA) and are often referred to as “paperweights.” Just be sure that the manufacturer of your 80% has an ATF “determination letter” that specifically states their paperweight is not a firearm.
Here’s some more from our end.
Note: The ATF raided Polymer80, an 80% manufacturer, in December 2020. There has been one reported case of the bureau also visiting a customer and forcing them to surrender their “P80.” Pew Pew Tactical is following the situation and will provide updates if there are any legal changes in the future.
Do I need to be an FFL to make a firearm?
The short answer is no as long as you meet the following criteria:
- Can legally own a firearm in your state/county/city (not a felon, etc…)
- Manufacturing only for personal use
- Configuration is legal in your state/county/city (National Firearms Act rules apply for short barreled rifles, automatics, etc…)
Do I need to put a serial number?
You as a private individual making a gun for yourself do not need to put a serial number. However, it’s helpful to have one in case it gets lost or stolen.
Why are they silver in color?
Most 80% lowers are sold as raw aluminum but you can also find some anodized which is the standard coating. However, when you complete an anodized 80%, all your cuts will expose the aluminum underneath. Therefore we recommend going with a raw lower and finish it afterwards.
Once you complete your lower, you can have it anodized or coated in other popular coatings such as Duracoat, Alumahyde, or even just spray paint if you’re feeling fancy.
How hard is it to finish an 80%?
You’ll need some specialized equipment such as a drill press, power drill, or a wood router, but an 80% AR-15 lower receiver is very doable for someone who has patience and some mechanical inclination. The AR-15 lower is quite forgiving since you are only machining out the pocket for the trigger and some pin holes.
*Update* Now you no longer need a mill or even a drill press…you only need a router and regular drill.
With some practice, you can get it done in under 2 hours!
Check out our favorites in Best 80% Jigs or our full review of the Easy Jig Gen 3 shown above.
Prices accurate at time of writing
Prices accurate at time of writing
25% off all OAKLEY products - OAKLEY25
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What are common 80% examples?
AR-15 80% Lower
The most common 80% lower receiver project out there.
Check out our favorite 80% AR-15 Lower Receivers.
AR-10/.308 80% Lower
The big brother of the AR-15, the AR-10 is another 80% project that is becoming more popular. It is very similar to the AR-15 in terms of difficulty.
Check out our favorite 80% AR-10 Lower Receivers.
AR-9 80% Lower
Relatively new to the market with the rise of pistol caliber carbines (PCC), a lot of jigs are set up to do both the AR-15 and AR-9 platforms.
Check out our favorite AR-9 80% Lowers.
The 80% lower version of Ruger’s venerable 10/22 from Tactical Machining is rarely in stock and has some more difficult steps since the barrel will mount directly to the receiver.
1911 80% Lower
Tactical Machining‘s newest 80% lower is the 1911. The difficulty level is quite high since you’ll be machining the slide rails which need to be near perfect. Almost all the other pieces of the 1911 also need to be hand-fit. They currently sell out in a few hours whenever they come into stock.
How do I complete an 80% lower?
We’ll be coming out with step-by-step 80% lower guides soon!
11 Leave a Reply
What I would like to know is, How do you tell 80% lowers apart? such as if you have an 80% lower that you don't know if it is 7075 t6 aluminum or if you have a 6061 t6 aluminum. if it is not marked? or if it just does not say which it is, or maybe you just do not know? also maybe to prevent a seller from trying to rip you off, and try to pass off 6061 as 7075, because their are no markings saying otherwise? How do you tell them apart from each other????
Very interesting article. When does the "step by step " come out?
It is illegal to assemble an 80% in NJ. It is considered manufacturing a firearm., specifically forbidden by state law.
In California, it seems we do have to add a serial # to any 80% build.
Great article, very informative, but I have a Question, how many 80 percent receivers are you allowed to build, Is there a limit? Thanks for all the great info, Mike klein
I have gotten into the 80% build for AR15 and 1911. Its lots of fun to build your own. Good info. Article is kind of an ad for Tactical Machining. There are lots of Other quality suppliers too. Im a fan of 80% Arms.
Keep up the good work Eric.
Dont have anyone work on our non-registered firearm...
Simple, true story
Once you complete a lower, you mention that you can have it anodized or coated in other popular coatings such as Duracoat or Alumahyde. My question is where can someone have this done? Is it still legal if you have someone else do the work, or will I need to figure out how to finish it on my own?
Hey Matthew, you'll have to call/search around. Some are FFL's so it could count as repair. Otherwise I believe you might have to wait there.
I don't build them because of big brother. I do them for the project and satisfaction. Heck, I have made several $700 guns for $1000 each. Definitely not the project for the budget minded.
Hello all. I guess I don't understand the 80% build out if your concern is that big brother knows what you have. Of course if you purchase new AR it goes through an FFL and record is made of you purchasing that particular rifle..... however, at least here in Pa, there is no requirement to use FFL to privately re-sell a non-NFA rifle and so should a day come when big bro says hand them over, the gov has no way to know what you still own or have sold.