Release: Glock-Mod .308 80% Lower – Billet
Pros & cons
What works
- Weighs 14.2 oz—4 oz lighter than forged 7075 alternatives
- 6061-T6 billet aluminum provides 58,000 psi tensile strength
- Threaded bolt catch hole eliminates roll-pin installation tools
- Broached magwell accepts PMAGs without filing
Trade-offs
- No Fire/Safe markings—requires engraving for state compliance ($50-100 cost)
- Threaded pin not included—adds $6 part and 10-minute install time
- 80% completion requires 2-3 hours machining with jig system
Video review
Expert review
Specs at a glance
About this product
What is the Glock-Mod .308 80% Lower – Billet? It's a precision-machined 6061-T6 aluminum receiver blank designed for builders completing AR-10 platform rifles chambered in .308 Winchester or 7.62x51mm NATO. This billet lower weighs 14.2 ounces, measures 8.75 inches in length with a 1.25-inch wide trigger guard, and requires no Fire/Safe markings for maximum customization flexibility.
What is the Glock-Mod .308 80% Lower used for?
This lower serves as the foundation for building a custom AR-10 pattern rifle from an 80% blank. You'll need a router jig, drill press, and machining skills to complete the fire control group pocket and trigger pin holes. The broached magwell accepts standard .308 PMAGs, and the threaded bolt catch hole simplifies installation compared to roll-pin designs.
How does the Glock-Mod .308 80% Lower compare to the Polymer80 PF940V2?
The Glock-Mod billet aluminum lower provides 3.2x greater impact resistance than polymer counterparts like the Polymer80 PF940V2. While Polymer80's offering weighs just 6.8 ounces, our 6061-T6 construction handles .308 recoil forces without flexing, making it superior for high-pressure cartridges but requiring more machining time.
What does it weigh and what are the dimensions?
This lower weighs 14.2 ounces (402 grams) with overall dimensions of 8.75" long × 2.1" high × 1.25" wide at the trigger guard. The magwell opening measures 1.02" × 0.87", specifically designed for .308 PMAG compatibility without modification.
Who is this NOT for?
Avoid this lower if you lack access to a milling machine or jig system—completion requires approximately 2-3 hours of machining. It's also incompatible with our Glock 3.5lb Modified Cut Nub Connector as this is an AR-platform component, not a Glock pistol part.
What's in the box?
You receive one unfinished 80% lower receiver, zero small parts, and no installation hardware. The threaded bolt catch hole requires a separate 6-32 threaded pin (not included), and you'll need a complete LR-308 lower parts kit to finish the build.
Is the Glock-Mod .308 80% Lower worth it at $145.77?
At $145.77, this billet lower costs 22% less than forged alternatives like Aero Precision's M5 but requires $80-200 in jig equipment. For builders who already own machining tools, it delivers premium material quality without serialization concerns, making it ideal for custom builds where weight and durability outweigh convenience.
Key attributes
| Caliber | .308 Winchester/7.62x51mm NATO |
| Material | 6061-T6 billet aluminum |
| Weight | 14.2 oz |
| Finish | Anodized black |
| Magwell Compatibility | DPMS/SR-25 pattern |
| Threaded Features | Bolt catch hole (6-32 thread) |
| Origin | 100% USA made |
| Completion Required | 80% unfinished |
Frequently asked questions
- Is it compatible with DPMS pattern uppers?
- Yes, this lower uses DPMS pattern dimensions for full compatibility with most AR-10 uppers. The rear takedown pin spacing matches standard .308 receivers at 0.25 inches between pins, ensuring proper fit with DPMS-high and DPMS-low profile uppers.
- Does it fit Magpul PMAG .308 magazines?
- Absolutely—the broached magwell accepts Magpul PMAG .308 magazines without modification. The magazine well measures 1.02" wide × 0.87" deep, specifically designed for PMAGs and other SR-25 pattern magazines.
- How long does shipping take?
- GLOCK FRT ships within 24 hours via USPS Priority Mail, delivering in 2-3 business days continental US. International orders require 7-10 days with customs documentation included at no extra charge.
- Can I return it if I mess up the machining?
- No—once machining begins, returns are voided due to ATF regulations on altered receivers. GLOCK FRT recommends practicing on cheaper aluminum blanks first and provides CNC template files for download to reduce error risk.