Polymer80Hub Exclusive: Billet .308 80% Lower Receiver

Build a real .308. Build it right. This isn’t a flimsy piece of kit. This is our solid billet 6061-T6 aluminum .308 lower, machined from a single block of American-made aluminum. It’s built for the long haul, for a rifle that needs to handle the power and pressure of the .308 Winchester/7.62x51mm round.

You get a clean, classic anodized black finish that fights corrosion and looks sharp. The magwell is professionally broached for smooth, reliable magazine changes every time. We’ve integrated a heavy-duty trigger guard—no flimsy tabs here—and the bolt catch hole is pre-threaded for a cleaner, stronger install (threaded pin required, included in our recommended LPK).

A Note on Compatibility: The AR-10/.308 platform isn’t as standardized as the AR-15. That’s why we strongly recommend you pair this lower with our dedicated LR-308/AR-10 Lower Parts Kit. It’s engineered for this receiver and includes the specific threaded bolt catch pin you need. Using random parts can lead to fitment headaches. Don’t make your build harder than it has to be.

Important Details:

• Material: 6061-T6 Billet Aluminum
• Finish: Type III Hardcoat Anodized, Black
• Markings: No Fire/Safe engravings. A clean slate for your build.
• Origin: 100% Made in the USA
• Platform: .308 / LR-308 / AR-10

WARNING: This is a component for manufacturing a firearm. You must complete this receiver in accordance with all federal, state, and local laws. It is your responsibility to know your laws. We cannot ship to restricted states or jurisdictions. Check our shipping page for current info, but laws change—you need to do your homework.

Prop 65 Warning: Products like this can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more info, see www.p65warnings.ca.gov.

Price: $141.90

Ready for a serious .308 build? Start with a solid foundation. This billet lower is it.