80% Lower Fire/Safe Marked – Anodized Black

Buy Polymer80 AR-15 80% Lower Fire/Safe Marked – Anodized Black: The Mil-Spec Foundation for Custom Builds in 2025

In the dynamic landscape of DIY firearm crafting, where every detail defines reliability and personalization, the Polymer80 AR-15 80% lower fire/safe marked anodized black emerges as the essential starting point for builders chasing perfection. As of November 2025, this isn’t merely an unfinished receiver—it’s a precision-forged powerhouse from 7075-T6 aerospace aluminum, Type III hardcoat anodized in matte black to mil-spec standards (MIL-A-8625), complete with deep-engraved “FIRE/SAFE” markings for seamless compliance and aesthetics. At Polymer80 USA, we’ve elevated the AR-15 80% lower game since 2016, blending affordability with unyielding durability to let you fabricate a rifle that’s yours alone—no FFL, no serialization until completion, just pure builder’s freedom.

Weighing a sturdy yet balanced 8.5 oz unfinished, this AR-15 80% lower fire safe marked features a broached magwell ready for PMAGs and STANAGs, pre-drilled pivot/takedown pin holes, and a threaded buffer tube housing for mil-spec compatibility. The bold, laser-etched safety engravings—visible through the anodized layer—ensure your finished build meets ATF expectations without extra work. Compatible with all standard AR-15 uppers, LPKs, and stocks, it supports 5.56 NATO, .300 Blackout, and 6.5 Grendel swaps, ideal for range plinkers, home defense setups, or 3-Gun competitors. Secure your Polymer80 80% lower anodized black for sale now—same-day shipping from our U.S. facility, with jig bundles under $200 for effortless milling.

What Is the Polymer80 AR-15 80% Lower Fire/Safe Marked – Anodized Black? Your Gateway to Custom AR-15 Ownership

The Polymer80 AR-15 80% lower fire/safe marked anodized black is an ATF-compliant unfinished receiver—80% complete, meaning the fire control group pocket is partially machined (drilled to 0.345″ depth) but requires your finishing to become a functional firearm. Forged from 7075-T6 aluminum for superior strength (83,000 psi yield), it’s then CNC-milled to ±0.001″ tolerances and hardcoat anodized black for corrosion resistance that endures 5,000+ hours of salt-spray exposure, per 2025 MIL-A-8625 validations from Precision Rifle Blog.

Evolving from Polymer80’s early polymer frames, this 2025 iteration incorporates deep “FIRE/SAFE” engravings—laser-etched post-anodizing for bold contrast—positioned on the left side for easy selector visibility. At 7.75″ long, 1.55″ wide, and 2.5″ tall (with trigger guard mounts), it includes a machined mag catch channel and integrated trigger guard provisions, making it a drop-in for mil-spec parts. Unlike raw blanks, the anodized finish matches factory uppers seamlessly, while the unfinished state preserves privacy—no background checks until you mill and serialize. For builders, it’s the blank canvas for AR-15s that blend mil-spec reliability with custom tweaks, from Geissele triggers to BCM uppers, delivering 1–2 MOA accuracy out of the box.

Key Features and Technical Specifications of the Polymer80 AR-15 80% Lower Fire/Safe Marked – Anodized Black

Elevate your build with features refined through 2025 user data from Sniper’s Hide and Pew Pew Tactical: The Polymer80 80% AR-15 lower anodized black isn’t basic—it’s engineered for endurance, with a flared magwell for swift reloads and reinforced pin lugs to withstand 10,000+ cycles.

• Forged 7075-T6 Aluminum: Mil-spec alloy for 30% higher strength than 6061, resisting fatigue in high-round-count sessions.
• Deep Laser-Engraved FIRE/SAFE Markings: Bold, contrasting etchings for compliance; visible under coatings like Cerakote.
• Type III Hardcoat Anodized Black Finish: Matte, non-reflective (MIL-A-8625); matches Aero/BCM uppers, resists scratches 2x better than Type II.
• Broached Magwell: Accepts all STANAG/PMAGs; 1.2″ flared entry cuts feed issues by 20% in drills.
• Pre-Drilled Holes: Front/rear pivot/takedown pins (0.154″ diameter), buffer tube threads (1-3/16″ x 16 TPI mil-spec).
• Integrated Trigger Guard Mounts: Snag-free for winter use; pairs with Magpul MOE guards.
• Mag Catch Channel: Machined for standard springs/detents; ambi-cut ready.

Full specs, cross-verified with 2025 mil-spec docs:

These ensure flawless integration with 95% of AR-15 components, from Toolcraft LPKs to Daniel Defense uppers.

Why Choose the Polymer80 AR-15 80% Lower Fire/Safe Marked – Anodized Black? Unmatched Compliance, Durability, and Builder Freedom in 2025

Amid 2025’s surge in DIY builds—fueled by ATF’s evolving ghost gun rules—the Polymer80 AR-15 80% lower fire safe marked shines for its ready-to-engrave compliance (deep markings simplify serialization) and anodized protection that outlasts raw forgings by 3x in corrosion tests (Pew Pew Tactical). Why over polymer like WarrHogg? Forged aluminum handles 5.56/.300 BLK pressures without warping, with 15% tighter tolerances than 6061 blanks for sub-MOA groups. The black finish eliminates post-milling refinishing, saving $50–100 on Cerakote, while privacy reigns—no FFL until you finish.

For 3-Gun pros, the flared magwell shaves 0.5 seconds off reloads; hunters appreciate the lightweight profile (under 7 lbs complete). Resale? Serialized builds command 25% premiums on Armslist. As a 2025 Military Arms Channel tester noted: “Polymer80’s anodized fire/safe lower is the compliant workhorse—matches my BCM upper perfectly after 2,000 rounds.” Select it for rifles that endure, not just impress.

How to Use the Polymer80 AR-15 80% Lower Fire/Safe Marked – Anodized Black: Finishing, Assembly, and Optimization Guide

Finishing your Polymer80 80% lower AR-15 anodized black is accessible, with 2025 protocols from 80% Arms yielding 45–75 minute sessions. Use an Easy Jig Gen 3 ($149 bundle) or Modulus router—no mill needed.

Usage Instructions for Finishing:

1. Setup (5–10 mins): Clamp jig to bench; insert lower (upside-down), torque screws to 10 ft-lbs. Use safety gear and cutting oil.
2. Drilling (10 mins): 5/16″ and 3/8″ bits for FCG pins (0.345″ depth); 1/8″ for selector—1,000 RPM max.
3. Milling (20–40 mins): Side pockets (0.275″ depth, 0.010″ passes with 3/8″ end mill), then pocket to 1.12″ depth. Deburr 400-grit.
4. Post-Process (5 mins): Inspect pins; re-anodize milled spots if desired (though hardcoat holds).

Assembly and Operation:

• Drop in LPK (Aero mil-spec, $40); torque pins 40 in-lbs.
• Install buffer tube/stock (mil-spec 1-3/16″ thread); add H1 buffer for .300 BLK.
• Mate upper; torque castle nut 38 ft-lbs. Dry-cycle 50x; zero at 50 yards with M193.
• Use: Load 5.56; clean post-200 rounds (bore snake, CLP on rails).

Tip: Pair with 1:7 twist barrel for 55gr varmint loads, hitting 1 MOA at 300 yards.

Safety Guidelines for the Polymer80 AR-15 80% Lower Fire/Safe Marked – Anodized Black

With 5.56’s 1,300 ft-lbs, safety is paramount: Triple-check chamber, enforce muzzle discipline, and use rated backstops. During milling, ventilate for aluminum dust; wear gloves. Post-build, torque fasteners quarterly; inspect engravings for legibility. Ammo: SAAMI-spec only—no steel-case in tight chambers. Storage: Unfinished in dry safe (<50% RH); completed locked from kids. ATF 2025: Personal serialization optional, but range practice mandatory.

Packaging, Storage, and Shipping: Polymer80 USA’s Builder-Centric Standards

Packaged in ESD-safe foam with desiccant and jig guide—raw edges protected, engravings highlighted. Anodized black units sleeved against scratches. Store horizontally in 50–70°F safe to maintain tolerances; avoid direct sunlight on finish.

Shipping: Discreet UPS/USPS, same-day pre-3 PM EST, insured $300. Free over $149; non-FFL direct-ship (18+). Blocks restricted states (CA, NY, NJ); ITAR for international ($50).

Our Services at Polymer80 USA: End-to-End Build Support

Your allies since 2016:

• 24/7 Support: Chat/email/hotline—milling queries resolved in 30 mins.
• Product Replacement: 60-day defects; 1-year structural warranty.
• Authenticity Guarantee: Forged batch-stamped; fakes? Refund + jig free.
• Technical Consultation: 15-min gunsmith calls for LPK matching.
• Complaint Handling: 24-hour escalation; 98% satisfaction.

Legal Considerations, Payment Options, and How to Buy Your Polymer80 AR-15 80% Lower Fire/Safe Marked

Legal: 80% unfinished (GCA/ATF 2025 compliant), 18+ no FFL—serialize post-mill for states like CO. Restricted: CA/NY precursors banned; we auto-screen.

Payments: Visa/AmEx/PayPal/ACH (1% off); crypto for discretion.

How to Buy: 1. Pick bundle (jig/LPK). 2. Cart with BUILD25 (10% off). 3. Secure checkout—ships tomorrow. Waitlist for low stock.

Real Testimonials and Customer Reviews: 2025 Builder Insights on Polymer80 AR-15 80% Lowers

From 2025 sources:

“Polymer80’s fire/safe anodized black lower milled flawlessly—matches my Aero upper, 1,500 rounds zero issues. Engraving pops!” – Range Enthusiast, TX (5/5, Pew Pew)

“Easy Jig finish in 50 mins; deep markings saved engraving hassle. Sub-MOA with BCM—best 80% AR-15 lower anodized value.” – 3-Gun Shooter, FL

“Hardcoat holds up to .300 BLK; flared well feeds PMAGs smooth. Polymer80’s the compliant king.” – Home Defender, OH

4.97/5 from 2,500+ reviews: “Mil-spec tough, builder-friendly.”

Frequently Asked Questions (FAQs): Polymer80 AR-15 80% Lower Fire/Safe Marked Essentials

Q: Fits mil-spec uppers? A: Yes—100% with Aero/BCM; 5.56/.300 BLK ready.

Q: Jig included? A: Bundles yes—Easy Jig Gen 3 recommended.

Q: Ships to CA? A: No—auto-blocked; polymer options available.

Q: Engraving depth? A: Laser-etched through anodize for durability.

Q: Anodizing affected by milling? A: Milled areas exposed—recoat optional.

Q: Weight vs. billet? A: 20% lighter forged—ideal for carbines.

More? 24/7 support here.

Limited Stock Alert – Grab Your Polymer80 AR-15 80% Lower Fire/Safe Marked – Anodized Black Today

2025 demand spikes fast—stock vanishes. Waitlist for restocks.

Launch your custom AR-15 with the compliant, durable Polymer80 80% lower fire safe marked anodized black—add to cart now and build boldly.