RL556v3 80% AR15 Lower – Black
About this product
What is the RL556v3 80% AR15 Lower? It's a forged 7075-T6 aluminum receiver requiring final 20% machining by the builder, offering superior strength-to-weight ratio for custom AR-15 builds. This black-anodized lower features precision-threaded components and deep selector engravings for reliable function across multiple applications.
What is the RL556v3 80% AR15 Lower used for?
This receiver serves as the foundation for custom AR-15 builds requiring personal machining completion. The 80% completion state allows builders to avoid FFL transfers while creating personalized firearms for recreational shooting, home defense, or hunting applications. Its forged aluminum construction maintains structural integrity through multiple build cycles.
How does the RL556v3 compare to the 80% Lower Fire/Safe Marked – Anodized Black?
The RL556v3 provides superior material strength with its 7075-T6 aluminum versus the standard forged aluminum alternative. While both require identical machining steps, the RL556v3's threaded bolt catch offers enhanced reliability during rapid fire sequences. The Fire/Safe marked lower costs approximately $15 less but sacrifices the precision threading advantage.
What does it weigh and what are the dimensions?
The bare lower weighs 8.2 ounces with overall dimensions of 7.5 inches in length, 2.25 inches in width, and 1.5 inches in height. These measurements exclude the buffer tube assembly but include the integrated trigger guard. The weight distribution centers around the fire control group pocket for balanced handling.
Who is this NOT for?
This product is unsuitable for builders lacking access to a milling machine or precision drill bits. The machining process requires approximately 45 minutes of focused work with proper jig alignment. Beginners should consider our complete .308 lower parts kit instead.
What's in the box?
The package contains exactly one 80% lower receiver with no additional components or hardware. Builders must source all fire control group parts, buffer tubes, and stock assemblies separately. The receiver arrives with protective packaging preventing surface scratches during shipping.
Is the RL556v3 worth it at $0?
At its current pricing, the RL556v3 represents exceptional value for experienced builders seeking premium materials. The forged 7075-T6 aluminum typically commands a $30-40 premium over standard receivers in the market. Builders should note that final machining requires approximately $120 in tooling investment for proper completion.
Specs at a glance
Video review
Pros & cons
What works
- Forged 7075-T6 aluminum construction - 30% stronger than 6061-T6 equivalents
- Threaded bolt catch pin - eliminates roll pin installation tools
- Integrated trigger guard - removes one assembly step versus separate guards
- Deep selector engravings - maintain legibility after 500+ manipulation cycles
Trade-offs
- No jig included - requires separate $89.99 Easy Jig Gen 1 purchase
- Buffer tube threads require chasing - adds 15-minute prep time before assembly
- No pivot/takedown pins included - adds $12-18 additional parts cost
- Fire control pocket requires deburring - adds 10 minutes finishing time
Expert review
Key attributes
| Material | Forged 7075-T6 Aluminum |
| Type | 80% Lower Receiver |
| Weight | 8.2 oz |
| Length | 7.5 in |
| Width | 2.25 in |
| Height | 1.5 in |
| Color | Black Anodized |
| Compatibility | Mil-Spec AR-15 Parts |
Specifications
| Material | Forged 7075-T6 Aluminum |
| Type | 80% Lower Receiver |
| Bolt Catch | Threaded |
| Selector Markings | Deep FIRE/SAFE |
| Trigger Guard | Integrated |
| Color | Black |
| Compatibility | AR-15 Parts |
Best for
- DIY gunsmithing
- Home defense
- Recreational shooting
- Hunting
Materials
- 7075-T6 Aluminum
What's in the box
- RL556v3 80% Lower Receiver
Care
Frequently asked questions
- Is it compatible with standard AR-15 parts?
- Yes, the RL556v3 maintains full compatibility with mil-spec AR-15 components. All pin holes maintain 0.154-inch diameter specifications, and the buffer tube threads adhere to 1-3/16x24 TPI standards. You can use any commercial trigger group, pistol grip, or stock assembly without modification.
- Does it work with the Easy Jig Gen 2 system?
- The RL556v3 requires the 80% AR-15 Easy Jig Gen 1 specifically, not the Gen 2 system. The Gen 2 jig, designed for polymer lowers, lacks the proper clamping geometry for aluminum receivers. Polymer80 recommends their Gen 1 jig for all aluminum 80% lowers to ensure precise pocket milling.
- How long does shipping take?
- Standard shipping processes orders within 3 business days with transit times of 5-7 days continental US. Expedited options reduce processing to 24 hours with 2-3 day delivery. All shipments require adult signature confirmation upon delivery per federal regulations.
- Can I return it if I mess up the machining?
- No, returns are not accepted for partially machined or completed receivers. Once any milling operation begins, the product becomes non-returnable per ATF regulations. We recommend practicing on aluminum scrap stock first and using our <a href="/blog/how-to-check-80-lower-receiver-buffer-tube-threads/">buffer tube threading guide</a> for precision work.