What is an 80% Lower Receiver?
An 80% Lower Receiver is an incomplete piece of aluminum that requires simple machining/drilling of the FCG (Fire Control Group) pocket which holds the hammer, sear, and trigger assembly. Unlike a firearm receiver it is not required to be transferred through a Federal Firearms Licensed holder (FFL).
Is This Legal?
Yes, in every state in the U.S., it is legal to build your own firearm for personal use, as long as you can legally own a firearm. You must build the Lower yourself. It is not legal for somebody else to do it for you. You are not required to engrave a serial number or any other information on the Lower, unless you later decide to sell it. From the ATF:
Individuals manufacturing sporting-type firearms for their own use need not hold Federal Firearms Licenses (FFLs). However, we suggest that the manufacturer at least identify the firearm with a serial number as a safeguard in the event that the firearm is lost or stolen. Also, the firearm should be identified as required in 27 CFR 478.92 if it is sold or otherwise lawfully transferred in the future.
Do I Need an FFL to Make a Firearm?
As long as you can legally own the firearm in the state, county and city you reside in you are allowed to manufacture a firearm for your own personal use. No serial number is required however it is suggested to engrave a serial number, model and manufacturer on your receiver in case it is lost or stolen.
All National Firearms Act (NFA) regulations apply to your firearm. You may create a short-barreled rifle out of your firearm via a BATFE (Bureau of Alcohol Tobacco Firearms and Explosive) Form 1 after BATFE approval.
If I Live in CA, are 80% Lowers Subject to the CA Assault Weapons Ban and Will I Need a Bullet Button?
80% Lowers are subject to all the same laws that apply to regular lower receivers. If you live in CA, you need to be careful to follow the laws related to the Assault Weapons Ban. In general, if you build AR-15 style rifle with a pistol grip, you will need a “bullet button”. There are configurations that do not require a bullet button. For more info on following CA Laws, Calguns.net has a very helpful flowchart: www.calguns.net/caawid/flowchart.pdf
How do I Finish an 80% Lower?
You do not need to have any machining experience in order to finish our 80% Lower Receivers. If you rent time on a CNC machine at a machine shop that hosts 80% Lower “Build Parties”, finishing your Lower is as simple as turning a couple bolts and pressing the “Start” button on the CNC Mill.
If you do not live close to a machine shop that is familiar with 80% Lowers, it is possible to finish a Lower using a Mill or Drill Press in conjunction with an 80% Lower Finishing Jig.
Completing an 80% Lower Receiver can be accomplished using a variety of methods, the most common methods require using a manual mill or a drill press. Most times, a jig or fixture is used to accurately machine the remaining 20% of the receiver. The most accurate way to complete you lower is using a CNC machine.
Overview of AR 15 AND 308 80% Lower Receiver
The amount of parts available on the commercial market allow for an unlimited number of combinations and configurations for any gun enthusiast. Most any mil-spec based commercial product for the AR 15 will work with our AR 15 80% Lower Receiver. The AR 15 80% Lower Receiver is a great starting point for many calibers including, but are not limited to: .223-5.56mm, 6.8 SPC, 7.62x39mm, 5.45x39mm, 6.5 Grendel. .50 Beowulf, 9mm, and .45 ACP.