Some of you may not have heard of an 80% lower and if so, no biggie we’ll explain it real quick. An 80% Lower is essentially a partially milled lower receiver for a firearm. Most often of the AR type, though not exclusively. As it is not completed it is not considered a firearm and can be shipped directly to your door (No FFL or paperwork). In order to actually utilize it you must finish milling it out with a drill press and/or router. This is absolutely legal and you do not have to register the weapon, at least from a Federal point of view. Please note states have their own set of laws regarding these and it is your responsibility to ensure you are not breaking any laws by constructing your firearm. There are plenty of resources out there to help you check your local laws and we are not lawyers here so you’re on your own with that.

Creator: Daniel6D | Source: Pixabay

My 80% Lower Project

If you are like me you may have known about 80% lowers for a while and just haven’t taken the leap into trying one out. I personally had wanted to build one for years but was slightly intimidated and just never got around to it. I’m relatively handy in the garage, but certainly not a machinist or even close so the idea of milling out a receiver seemed like I would likely be throwing money away on a failed effort. I can now tell you that this is not the case. The cost is relatively cheap (you can get lowers around 50USD) and you can easily knock it out in an afternoon. The one exception to the cost is I would recommend purchasing or borrowing a good 80% lower jig. This really does make it a straight forward and simple job. Once you’ve tried it out and decide it’s something you’d like to continue to do then you can spring for a good quality jig. Mine runs around $300.00. Now that I have knocked one out I plan on doing many more, and I think many of you will really enjoy it too. Let alone the prize of building out your custom firearm in the end.

I cover it in the video, but I utilized an Easy Jig Gen 2. Pictured and linked below is the current version which is the Easy Jig Gen 3 Multi-Platform – AR-15, AR-9 and .308 80% Lower Jig, which as you can see handles multiple platforms. You can get it or learn more about it HERE 

About the Video Series Below

In the nine videos below I run you through the entire process as I build my first lower. It is worth mentioning again this is my first time doing this. I’m not an expert, nor do I claim to be. That said I believe there is value in watching them (if you want to do one) as I run you through each step of the process and share some of my lessons learned along the way. Please feel free to ask your questions in the comment links below and I’d be happy to help where I can. Likewise for those of you who are well seasoned at this process please feel free to share some of your expert tips with the community below as well. 



Ok  Let’s get to it!

Introduction and Inventory

Setting Up the 80% Lower Jig

Configuring the Router for the milling process of the 80% Lower

Pilot Hole on the 80% Lower Explained

Drilling out the 80% Lower Pilot Hole

Final 80% Lower Mill Prep and Shop Vac talking points

Milling out the 80% Lower

80% Lower Mill review and Trigger Pocket Setup

Drilling out the final Holes on the 80% Lower

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