H&K MR556 A1 Features
A direct descendant of the world-famous HK416, the MR556A1 is the commercial carbine from the same DNA. It offers the battlefield-proven reliability, durability and precision you would expect from a rifle that bears the name Heckler & Koch. The MR556A1 is assembled in the USA using US and German-made components and uses many of the same parts and assemblies developed for the HK416. Like the HK416, the MR556 A1 uses a proprietary HK short-stroke gas piston in place of the direct-gas-impingement system found on lesser AR15-style rifles that propels exhaust gas into the upper receiver to operate the action. In the “closed” HK piston system, exhaust gasses never enter the receiver, which means the HK runs cooler, cleaner and more reliably. When adverse conditions, like dust, sand and mud are introduced, the advantage of the HK system becomes even more drastic. That is why so many of the worlds elite military and law-enforcement customers have absolute trust in their HKs.
H&K MR556 A1 Specifications
- Brand: HK
- Category: Tactical Rifles
- Series: A1
- Caliber: 5.56x45mm NATO
- Model: MR556
- Stock Finish Group: Black
- Capacity: 30+1
- Stock Material: Synthetic
- Action: Semi-Auto
- OAL: 33.90″- 37.68″
- Hand: Right
- Sights: Optic Ready
- Twist: 1:7″
- Gun Platform: AR-Style
- Magazine Type: OEM
- Grips: Black Polymer
- Handguards: M-LOK
- Receiver Material: Aluminum
- Stock Description: Adjustable
- Barrel Description: Medium Contour
- Barrel Length: 16.50″
- Max Capacity: 30
- Receiver Finish: Black
- Weight: 8.60 lbs
- Stock Finish: Black
| Barrel Length | 16.5 | 
|---|---|
| Caliber | 5.56 | 
| Capacity | 30 | 
| Condition | New in Box | 
| Finish Per Color | Black | 
| Manufacturer | Heckler and Koch | 
| Manufacturer Part Number | 81000579 | 
| Model | MR556 A1 | 
| Type | Modern Sporting Rifles | 
| UPC | 642230262553 | 
Frequently Asked Questions About This Product
Why buy Heckler and Koch MR556 A1 5.56 NATO 16.5" Barrel 30-Rounds Optics Ready 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 Heckler and Koch MR556 A1 5.56 NATO 16.5" Barrel 30-Rounds Optics Ready?
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 Heckler and Koch MR556 A1 5.56 NATO 16.5" Barrel 30-Rounds Optics Ready 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: Modern Sporting Rifles, RIFLES.
What tags or features does this product have?
Key features and tags for this product include: Modern Sporting Rifles, RIFLES.
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.
FFL Transfer & Firearms Laws for Heckler and Koch MR556 A1 5.56 NATO 16.5" Barrel 30-Rounds Optics Ready
All firearms, including the Heckler and Koch MR556 A1 5.56 NATO 16.5" Barrel 30-Rounds Optics Ready, 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 Heckler and Koch MR556 A1 5.56 NATO 16.5" Barrel 30-Rounds Optics Ready 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.

 
				
 
				 
				 
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