HK USA MR556 A4 5.56x45mm 30 Round Capacity Semi-Automatic Rifle

HK USA MR556 A4 5.56x45mm Semi-Automatic Rifle

The HK USA MR556 A4 stands as a testament to Heckler & Koch’s commitment to engineering precision and operational reliability. Derived directly from the combat-proven HK416 platform, the MR556 A4 is a compact 5.56x45mm rifle engineered for discerning operators and competitive shooters who demand uncompromised performance. This platform integrates HK’s proprietary short-stroke gas piston system, enhancing performance parameters beyond conventional direct impingement designs.

Key Features

Advanced Operating System

The MR556 A4 utilizes HK’s renowned short-stroke gas piston operating system. This design significantly mitigates carbon fouling in the receiver and bolt carrier group, resulting in cooler internal temperatures and extended operational reliability between cleaning cycles. The self-regulating piston system ensures consistent cycling across a spectrum of ammunition types and environmental conditions, providing a robust and dependable firing sequence.

Cold Hammer-Forged Barrel

This variant features an 11-inch cold hammer-forged barrel, constructed from a high-grade steel alloy. The cold hammer-forging process densifies the barrel steel, enhancing its structural integrity and longevity. This manufacturing technique contributes directly to the barrel’s inherent accuracy potential and its resistance to bore erosion, ensuring consistent shot placement over its service life.

Robust Construction

The MR556 A4 is built with precision-machined upper and lower receivers, fabricated from durable aerospace-grade aluminum. All critical components are engineered to resist corrosion and withstand the rigors of extensive use. The rifle is presented in a practical Grey (GRY) finish, offering both aesthetic and protective qualities.

Ergonomics and Modularity

Designed for practical utility, the MR556 A4 incorporates a free-float handguard, allowing for direct attachment of ancillary equipment without impacting barrel harmonics. The design maintains compatibility with a wide array of AR-style accessories, enabling operators to customize the platform to specific mission requirements or competitive disciplines. An adjustable stock provides an optimized interface for diverse shooter anatomies and tactical applications.

Technical Specifications

• Model: HK USA MR556 A4
• Caliber: 5.56x45mm NATO (.223 Remington compatible)
• Barrel Length: 11 inches
• Capacity: 30+1 Rounds
• Operating System: Short Stroke Gas Piston
• Finish: Grey
• SKU: LIP|HK81001312
• Price: $3749.00