Maxim Defense MDX 516 5.56 16″ 30rd Gray
The maxim defense mdx 516 5.56 16″ 30rd gray is a factory-built AR pistol chambered in .223 Rem / 5.56 NATO with a 16-inch barrel and a 30-round magazine. The urban gray finish and M-LOK handguard make it ready for range sessions, training, or custom builds right out of the box.
| Manufacturer | Maxim Defense |
|---|---|
| Model | MDX 516 |
| Material | 7075-T6 aluminum upper and lower receiver (per manufacturer specs) |
| Compatibility | .223 Rem / 5.56 NATO ammunition |
| Finish | Urban Gray anodized |
| Weight | 6.2 lbs (with empty magazine, per manufacturer specs) |
| Condition | New |
Key Features
- 16-inch barrel with mid-length gas system — WHY IT MATTERS: This barrel length and gas system combination gives you a softer, more controllable recoil impulse, which helps new shooters stay on target and makes follow-up shots quicker.
- M-LOK compatible handguard — WHY IT MATTERS: You can attach lights, lasers, or a foregrip exactly where your family members need them, without adding unnecessary weight or bulk.
- 30-round magazine included — WHY IT MATTERS: You get a full-capacity magazine right in the box, so you can head straight to the range without buying extra gear.
- Urban gray anodized finish — WHY IT MATTERS: The gray finish resists scratches and corrosion better than basic black, and it looks distinctive on the range or in the safe.
- Factory-built semi-auto action — WHY IT MATTERS: It comes ready to shoot from the factory with a reliable semi-auto action, so you don’t have to worry about building or troubleshooting your first AR pistol.
Who It’s For
This MDX 516 is for families who want a do-it-all AR pistol for range fun, home defense training, or as a base for future upgrades. It also fits youth shooters moving up from rimfire rifles — the 16-inch barrel and mid-length gas system reduce recoil and muzzle rise. Beginners will appreciate the simple, ready-to-shoot package.
Pros and Cons
Pros: Reliable factory build, gray finish stands out, M-LOK handguard for accessories, softer recoil with mid-length gas system.
Cons: Price is higher than some entry-level AR pistols, and the 16-inch barrel makes it longer than typical pistol-braced ARs (though it still qualifies as a pistol under current ATF rules).
Comparison
| Feature | Maxim Defense MDX 516 | Geissele Super Duty 16″ | Zev Technologies OZ9C |
|---|---|---|---|
| Caliber | .223 Rem / 5.56 NATO | .223 Rem / 5.56 NATO | 9mm |
| Barrel Length | 16″ | 16″ | 4.5″ |
| Action | Semi-auto | Semi-auto | Semi-auto |
| Handguard | M-LOK | M-LOK | M-LOK |
| Finish | Urban Gray | Black / DDC | Black / FDE |
| Weight | 6.2 lbs | 6.7 lbs | 2.4 lbs |
| Price | $2,425.50 | $1,950 | $1,800 |
FAQ
What is the barrel twist rate on the Maxim Defense MDX 516?
The MDX 516 uses a 1:7 twist rate barrel, which stabilizes both 55-grain and 77-grain 5.56 rounds effectively.
Does this come with a pistol brace or stock?
It ships with a Maxim Defense pistol brace (the PDW brace) installed. The 16-inch barrel keeps it in pistol configuration under current ATF guidelines.
Can I swap the handguard for a different length?
Yes, the M-LOK handguard is removable and compatible with standard AR-15 barrel nuts, so you can swap it for a different length or brand of handguard if you prefer.
Is this California legal?
No, the 30-round magazine and semi-auto pistol configuration do not comply with California’s assault weapon laws. We ship to all 50 states, but you must follow your local laws.
Trust Block
- ✅ Nationwide delivery (all 50 states)
- ✅ Ships 1-2 business days
- ✅ 30-day returns
- ✅ Secure checkout
Last updated: April 2026
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FFL Transfer & Firearms Laws for Maxim Defense MDX 516 5.56 16″ 30rd Gray
All firearms, including the Maxim Defense MDX 516 5.56 16″ 30rd Gray, must be shipped to a licensed Federal Firearms License (FFL) dealer. You will be required to complete a background check and any necessary paperwork before taking possession.
How It Works
- Place your order online.
- Provide your preferred FFL dealer information.
- We ship the firearm directly to your FFL.
- You complete the background check and pickup at the FFL.
Legal Compliance
We comply with all federal and state firearm laws. It is your responsibility to ensure the Maxim Defense MDX 516 5.56 16″ 30rd Gray is legal in your state. Some states may have restrictions on certain firearm models or features.
Helpful Resources
Need assistance? Contact our Miami store for help with FFL transfers and firearm compliance.
Frequently Asked Questions About This Product
Why buy Maxim Defense MDX 516 5.56 16″ 30rd Gray from Miami Shooters Supply?
We’re a trusted firearms dealer offering fast shipping, competitive pricing, and 100% compliance with U.S. federal firearm laws. All orders ship from our licensed facility with full tracking and expert customer service.
Where can I buy Maxim Defense MDX 516 5.56 16″ 30rd Gray?
You can purchase this item directly on our website and have it shipped to your local FFL dealer. You can also visit us in-store in Miami, Florida.
Is Maxim Defense MDX 516 5.56 16″ 30rd Gray available now?
Availability is shown live on this page. If the “Add to Cart” button is visible, this item is currently in stock and ready to ship.
What category does this product belong to?
This product is listed under: AR Pistols.
What tags or features does this product have?
Key features and tags for this product include: .
Is this product legal in my state?
It is your responsibility to ensure this item is legal in your state or locality. We ship only to valid FFL dealers in compliance with U.S. laws. Always check your local regulations.
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FFL Transfer & Firearms Laws
All firearms, including the Maxim Defense MDX 516 5.56 16″ 30rd Gray, must be shipped to a licensed Federal Firearms License (FFL) dealer. A background check and any required local paperwork must be completed before you can take possession.
How It Works
- Place your order online.
- Send us your preferred local FFL dealer info.
- We ship the firearm to your FFL after verification.
- Complete background check and pick up from your dealer.
Legal Compliance
We comply with all U.S. firearm laws. It is your responsibility to ensure the Maxim Defense MDX 516 5.56 16″ 30rd Gray is legal in your state. Some states (e.g. CA, NY, NJ) have restrictions on magazine size or certain features.
Helpful Links
Need help? Contact our team — we’ll guide you through selecting a compliant firearm and the FFL transfer process.
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