Lifetime Warranty Lifetime Warranty Made in the USA Made in the USA FREE Shipping on $250+ Free Shipping on all orders $250+! – 80% Lowers, 80% Lower Jigs & AR-15 Parts

4 Ways to Complete an 80 Lower Receiver

An 80 Lower Jig allows users to complete an AR-15 80% lower

The 80% lower receiver (like our billet and forged receiver blanks) is one of the easiest ways to build an AR-15. Building at home requires no FFL paperwork or background check, according to the ATF. That means you get to save money. No special taxes, no extra fees, no hassle.

But how do you complete an 80 lower receiver, anyway? The fact that you are the one actually making the firearm – milling and drilling your lower with a jig – is just one reason so many AR lovers are choosing to build their next black rifle or pistol an 80 lower.

If you’ve never attempted to complete an 80% lower, you might think it’s too difficult for you. But the lower can be completed in a multitude of ways, using a variety of tools. And it does not require exceptional skills.

4 way complete an 80 lower receiver

While the average AR-15 builder may not have access to all the tools mentioned here, he or she should have access to at least one or more. These various ways of completing an 80 lower receiver will help you understand what you need or can use to complete your 80 lower.

1. 80 Lower Jig

The Easy Jig Gen 2 works with AR-15 and AR9 80 lower receivers
The Easy Jig Gen 2 works with both AR-15 and AR9 80 lowers.

The 80% lower jig was specifically designed for completing AR-15 receiver blanks! We’re talking about the jig first because it’s probably how you’ll get the job done.

Here’s our tutorial that shows you how to complete an 80% lower with a jig.

An 80 Lower Jig acts like a miniature milling machine and drill press bench top, right in your garage or basement. The 80 Lower Jig uses individual guide plates and a router attachment plate to drill and mill out the lower’s fire control group.

The Porter Cable Handheld Laminate Router, designed for completing 80 lower receivers
Many 80 lower jigs were specifically designed to use the Porter Cable 6430. We offer it with a nice little discount!



The best part of the jig is that it does all the measuring for you. The guide plates automatically “measure” the pocket you need to mill, and a drill depth guide even tells you how far you have to go.

Essentially, the jig does all the work! All you need to do is act as the “machine”. You’ll be using a handheld router and a hand drill to complete it.

This only takes around 1 to 2 hours, even 15 minutes for pro builders (using the Router Jig PRO from 5D Tactical, which is considered the fastest jig).

2. CNC Machine

An automated machine tool operated by computer numerical control (CNC) is often referred to as a CNC machine. These computer-aided tools are controlled by computer-aided design (CAD) and computer-aided manufacturing (CAM) programs. By using a CNC machine, the process of completing an 80 lower will be automated and offer precision machining.

For those who have access to a CNC machine, there are various CAD programs available online to complete your 80 lower receiver. These CAD programs will allow you to program the CNC machine in order to complete your 80% lower to MilSpec standards.

Pros: The pros of using a CNC machine are the elimination of human error and precision manufacturing. Once the CAD program is installed and X, Y and Z-axis are established, the CNC machine has the ability to complete the 80% lower with precision.

Cons: The CNC machine will require adequate knowledge of CAD programming and CNC machine operation. Unfortunately, most individuals do not have access to a CNC machine.

3. Milling Machine

A milling machine is designed to machine solid materials such as metal and wood. Depending on make and model, milling machines can either be automated, CAD directed or manually operated. Milling machines are capable of multi-axis machining and offer precision capability even if operated manually.

Pros: A milling machine will offer precision milling of your AR-15. Even with limited knowledge in machining, milling machine basics can be learned very quickly. If you have access to a milling machine, ask the owner to teach you some basics. With just a few basic skills you can complete your 80 lower using the precision milling capabilities of the milling machine.

Cons: Milling machines do require a learning curve. Not everyone will be comfortable learning how to operate a milling machine and its dynamic capabilities may be somewhat intimidating. Depending on your skill level, a milling machine will offer superior capabilities.

4. Drill Press

A drill press is a pedestal style drill that is mounted to a stand. Most portable style drill presses have a spindle and chuck that moves parallel to the axis of the pedestal. Most drill presses will be operated manually, although they will allow for setting of various depths when drilling or milling. The drill press can also provide for the mounting of a vise or clamp in order to securely hold your 80 lower receiver while drilling and milling.

Pros: A drill press is the simplest way to complete your AR lower. With limited knowledge and skills most anyone can complete an 80 lower with drill bits and end mills. The drill press is also economical and most individuals will have access to a drill press.

Cons: A drill press will not provide the precision machining of a CNC machine or milling machine.Although, if done correctly (and by using a drill press vise), most people will not be able to tell your lower receiver was completed on a drill press.

4 Ways to Complete an 80 Lower Receiver
Article Name
4 Ways to Complete an 80 Lower Receiver
You want to build your next AR with an 80% lower, but how do you do it? With a jig? a drill press? Here are 4 ways to complete an 80 lower receiver.
Publisher Name
Publisher Logo

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 AR-15LowerReceivers, 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.


Get exclusive discounts on AR-15 gear and be the first to know about new product releases.

The BEST Builds Start
with the BEST Parts

Customer Service is our passion and we are here to answer any questions you have.
(888) 581-0750

Shop With PRIDE

Shop With Confidence

Secure Payment