Introduction
If you’re in the market for quality firearm components, you’ve likely come across the term RKS lower housing. Whether you’re a hobbyist, builder, or professional, understanding what this component does, how it works, and how to choose the right one is essential.
This article offers a complete, easy-to-read guide. We’ll cover its function, features, materials, legal considerations, and how it fits into your rifle build.
What Is an RKS Lower Housing?
The RKS lower housing is a part of a firearm, specifically in rifles like the AR-15 or similar platforms. It’s also called the lower receiver or just “lower.” This part houses many of the core mechanisms:
- Trigger group
- Magazine well
- Bolt catch
- Safety selector
- Buffer tube attachment point
The lower receiver is usually considered the “firearm” by law. This makes it a critical piece in any build or repair project.
Why RKS Lowers Stand Out
RKS has developed a reputation for high-grade materials and precision engineering. Unlike some generic brands, RKS parts are designed to meet the needs of both civilian users and tactical professionals.
Key reasons why RKS lowers are popular:
- Aircraft-grade aluminum materials
- Tight tolerances for consistent fit
- Compatibility with Mil-Spec components
- Anodized or Cerakote finishes for durability
- Lightweight and strong construction
This attention to detail makes RKS a trusted name in the firearms community.
Types of RKS Lower Housings
RKS offers a few different styles depending on your intended build or customization. The most common types include:
1. Stripped Lower
This is a bare housing unit. It contains no internal parts and is ideal for those building a rifle from scratch.
2. Complete Lower
Includes all the fire control parts, buffer tube, and sometimes even the stock. A plug-and-play option.
3. 80% Lower
This is unfinished. It requires machining before it’s considered a firearm by law. It’s popular among DIY builders.
Each type has pros and cons, depending on your skill level and goals.
Materials Used in RKS Lowers
The most common material used in RKS lower housing is 7075-T6 aluminum. This is the same grade used in aircraft manufacturing. It offers high strength and low weight.
Other materials include:
- 6061-T6 aluminum – Still strong, but less so than 7075. Often used in budget models.
- Polymer – Lighter but less durable under stress. Suitable for lightweight builds.
- Billet vs. Forged – Forged lowers are lighter and stronger. Billet lowers offer unique looks but is heavier.
RKS typically sticks with forged 7075-T6 for durability and reliability.
How It Fits into a Rifle Build
The lower receiver is where most of the rifle’s action happens. It’s where you insert your magazine, pull the trigger, and where your buffer tube and stock connect.
When building a rifle:
- Choose your lower–stripped or complete
- Install lower parts kit (LPK) – includes pins, springs, and trigger
- Attach buffer tube and stock
- Mate it to an upper receiver using takedown pins
The RKS lower housing is compatible with most Mil-Spec uppers, giving you flexibility in your build.
Legal Aspects of Purchasing a Lower
One key detail about lower receivers is that they are legally considered a firearm. This means:
- You need to buy it through a licensed FFL dealer
- You must complete a background check
- Serial numbers are required
- 80% lower is not regulated until completed
Always follow federal, state, and local laws before buying or modifying a lower receiver.
RKS Lower vs. Other Brands
What sets RKS apart from other brands? Let’s compare them based on several factors:
| Feature | RKS Lower Housing | Generic Lower |
|---|---|---|
| Material | 7075-T6 forged | May vary |
| Finish | Hardcoat anodized | Basic anodizing |
| Compatibility | Full Mil-Spec | Limited in some |
| Machining Precision | Tight tolerances | May need fitting |
| Warranty/Support | Usually included | Varies widely |
If you want reliability, ease of use, and longevity, RKS is often a better investment.
Installation Tips
Installing your RKS lower is straightforward, but here are a few tips:
- Use a quality punch set and a vise block
- Follow a lower parts kit (LPK) diagram
- Grease small pins and springs for easier installation
- Avoid over-torquing the buffer tube
- Confirm the proper function of the trigger and safety selector
This will ensure a clean and safe installation.
Maintenance & Cleaning
Keeping your RKS lower housing in top condition is easy:
- Wipe it down regularly with a gun cloth
- Use compressed air to clean out dust and grit
- Inspect your trigger group for wear
- Lightly lubricate pivot points
- Store it in a dry, secure case
Proper care ensures long-lasting performance and prevents malfunctions.
Common Problems & Solutions
Here are a few issues users might face:
- Loose fit with upper: Check takedown pins and receiver dimensions
- Trigger not resetting: Inspect spring installation
- Safety selector feels tight: Add lubrication or adjust detent
- The magazine won’t seat: Try different magazines or inspect Magwell
Most issues are minor and easy to resolve with attention to detail.
Where to Buy RKS Lower Housing
You can find RKS products at:
- Local gun stores
- Online firearm retailers
- Gun shows and expos
- Direct from RKS (if available)
Always check that you’re buying from an authorized dealer. Look for proof of authenticity and warranty details.
Conclusion
The RKS lower housing is crucial for anyone looking to build or upgrade their rifle. It offers excellent material quality, superior fit, and long-lasting reliability.
Whether assembling your first AR-15 or fine-tuning your tactical setup, RKS lowers give you a solid foundation. Follow legal guidelines, choose the right model, and maintain it properly.
A reliable lower housing isn’t just a part—it’s the backbone of your rifle build.
Frequently Asked Questions
Is RKS lower housing compatible with all AR-15 uppers?
Yes, most RKS lowers are Mil-Spec and work with all Mil-Spec AR-15 uppers.
Can I use an RKS 80% lower without a license?
Yes, but only if you machine it for personal use. It becomes a firearm after completion and must comply with local laws.
Does the RKS lower housing come with parts installed?
Only if you buy a complete lower, stripped lowers do not include internal parts.
What tools do I need to install a lower parts kit?
You’ll need roll pin punches, a small hammer, and a vise block.
Can I install a custom trigger in my RKS lower?
Absolutely. RKS lowers are built to accommodate most aftermarket triggers.
