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300-blackoutupper-com: 80% Lowers, Jigs, Build Kits & More! – 80 Lower Jig

Review: Premium 300 BLK Billet Black 80% Lower

There’s a lot of buzz about building black rifles at home, and many folks have been assembling their .223 and 5.56 ARs in the comfort of their garages and basements for quite some time. With the introduction and rising popularity of 300 BLK, we only figured it’s fitting that we review the core of the idea of building your own 300 Blackout rifle or pistol at home: The 80% lower.

Our premium billet 80% lower, to be exact. It’s one of the most popular currently available on the AR 15 market, and for good reason. Let’s dive into why it’s the perfect starting point for building your own 100% legal, home-finished 300 BLK gun without dealing with the red tape and FFL paperwork.

Premium Black 80% Lower Billet Fire/Safe Engraved & Easy Jig Gen 1 with Tooling

You can have our Premium 80% Lower shipped to your door with the required jig and tools! No FFL is required for this lower and jig combo kit!

The Premium 80% Lower’s Features

Machining your own 80% lower into a finished receiver that should be capable of hosting a lower parts kit and ultimately firing a live round can sound intimidating, especially with the big ole’ nasty 300 BLK. So, we’ve made the whole build process easier.

For starters, we’ve included a threaded bolt catch release hole and a threaded rear takedown detent hole. If you’ve never built an AR 15 lower receiver before, we’ll clue you in: These two pain points have been the cause of so much frustration, missing springs, and calls to parts makers for replacement parts.

What once required a punch and lots of patience now simply requires the twist of some threads! A process that once took 2 hours now takes about 5 minutes. The screws and hex keys are included for an easy install, too.

Billet Construction Makes Machining Easier

There are two popular lower fabrication methods: Billet and forged. While forged lowers sound sexy and while they may seem a bit more rugged, the billet lower is the best option for first-time builders. Our billet lower is made of premium 6061 T6 aluminum, and its billet construction makes machining easier and faster, with less chance of mistakes.

AR-15 / Premium Lower Parts Kit

When paired with our Premium Lower Parts Kit, your finished 80% Lower will provide the best trigger and shot group potential possible.

If you were nervous about taking a router to raw metal, fear not – we’ve made it super easy. This lower even features pre-engraved Fire and Safe indicators to ensure safety once finished and ready to fire.

Broached Mag Well and Heavy-Duty Trigger Guard

Our billet receiver features a uniquely designed, broach mag well. While aesthetic, it also provides more functionality and easy loading. This lower accepts all standard AR 15 magazines, and by-design 300 BLK magazines! Just because this lower is billet doesn’t mean it’s not rugged. A reinforced trigger guard ensures this lower will be able to withstand plenty of abuse.

Fits with Any Available 300 Blackout Upper

Our billet lower is precision machined to ensure it’s compatible with every 300 Blackout rifle and pistol upper, and complete built kit we sell. What’s more, this lower requires no FFL because it is not considered a firearm until you finish building it! You can verify this by checking the Gun Control Act of 1968 against the federal definition of a firearm, 18 U.S.C. 921(a)(3). Any other questions? Just call and ask!

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 300-blackoutupper, 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.


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