Finish or upgrade your stripped lower or fabricated 80% lower.
Finished your 80% lower? Grabbed a stripped receiver that you're ready to assemble? We've got you covered with all the AR lower assembly components you need -- or want to upgrade! Check out the mil-spec LPKs we have in stock. They work with all fabricated 80% units and every mil-spec "retail" lower on the market, including the various calibers you might own: 9mm, 5.56, .223, .308, 300 BLK and more.
The stock AR trigger gets the job done, sure. But you can enjoy better shot placement and a more ergonomic grip with a few easy drop-in upgrades. We've partnered with Rise Armament, JMT, PSA, Hogue, and other top AR parts makers to offer up some of the best upgraded AR triggers and grips available for the AR platform.
Installing the lower parts kit in your stripped receiver or fabricated 80% lower is relatively easy. Some basic tools are required, which include:
Need help? Here's our detailed lower parts kit install guide!
You'll need the following parts, which can all be found right on this page or by clicking the links below to filter products by type:
Not sure what to buy? Here's our complete parts guide to building the AR-15.
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 GunBuilders.com, 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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