Common Myths about Building an AR-15 with 80 Percent Lowers

Posted by 80-Lower on Jan 27th 2019

Common Myths about Building an AR-15 with 80 Percent Lowers

“That’s illegal!”. “The finished gun is going to be junk”. “Oh, that’s not compatible with regular AR stuff”. If you’re reading this, then you may have been assaulted by some unfortunate myths about building an AR-15 with 80 percent lowers. We’re here to dispel some of those myths – including all the legal hocus-pocus that’s simply incorrect.

Myth #1: Building an AR-15 at home is illegal

*Buzzer*. Wrong. Building an AR-15 at home with an 80 percent lower is 100% legal! The Bureau of Alcohol, Tobacco, and Firearms couldn’t make this myth any more false. Their own literature is pretty plain about the whole ordeal:

Does an individual need a license to make a firearm for personal use? No, a license is not required to make a firearm solely for personal use. 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.

[18 U.S.C. 922(o), (p) and (r); 26 U.S.C. 5822; 27 CFR 478.39, 479.62 and 479.105]”

So, there it is: If you’re building an AR-15 at home with parts made in America, and you don’t plan to sell it, you’re good to go. DISCLAIMER: You must be sure your AR-15’s features and configuration meets your local and state laws.

Myth #2: You need to fill out paperwork to build an 80 Percent Lower

Wrong again! Well, in most cases. Nothing in the ATF’s books dictates that you need to submit any paperwork to the Federal government before you build a firearm at home. You do not need to have a background check conducted, you don’t need an FFL transfer to receive or complete your 80 percent lower, and you don’t need to pay any fees.

Some states, however, do require paperwork. California, for example, requires that you submit paperwork for an assigned serial number – which adheres to its own set of regulations – before you build your 80 Percent Lower. Again, check your local and state laws first.

Myth #3: An 80 Percent Lower isn’t Compatible with Regular AR-15 Parts

This one’s also mostly wrong. As far as conventional .556- and 2.23-chambered AR-15s go, all 80 percent lowers are compatible with all AR-15 parts. That means triggers, barrels, chambers, uppers, buffer tubes, buttstocks, and everything else under the black rifle sun will work fine with your 80 Percent Lower.

Some .308-chambered 80 percent lowers will require parts that are compatible with DPMS’s Gen 1 platform. This is because the Armalite AR-10 platform is different from the DPMS LR-308, though this has been a known fact well before the creation of the 80 percent lower.

Myth #4: 80 Percent Lowers are Unreliable

Wrong! In fact, the reliability of your completed AR-15 lower receiver rests entirely in your hands. You get to be the manufacturer, the quality control specialist, and the final tester. That means you have complete control over just how reliable, accurate, and ergonomic your finished AR-15 is.

All our 80 Percent Lowers are 100% made in the U.S.A. from billet 6061 T6 aluminum or forged 7075 T6 aluminum. All 80 Percent Lowers include a Limited Lifetime Warranty.

DISCLAIMER: If you are new to the world of DIY gun building, you likely have a lot of questions and rightfully so. It’s an area that has a lot of questions that, without the correct answers, could have some serious implications. At, we are by no means providing this content on our website to serve as legal advice or legal counsel. We encourage each and every builder to perform their own research around their respective State laws as well as educating themselves on the Federal laws. When performing your own research, please be sure that you are getting your information from a reliable source.