The HK MR556 A4 and MR762 A4 represent the latest evolution of the legendary HK416 platform, delivering unmatched performance, precision and durability. Designed for shooters who demand no-compromise reliability, these rifles embody Heckler & Koch's elite engineering and battlefield-proven excellence. At the core of their superior performance is HK's short-stroke gas piston system, which virtually eliminates hot carbon fouling in the action. This enhanced system allows the rifle to run longer, with less maintenance and reduced wear on internal components compared to traditional direct-impingement ARs. The adjustable gas regulator ensures seamless tuning for both suppressed and unsuppressed operation, giving operators greater control in any environment. Designed with ergonomics and versatility in mind, the fully ambidextrous controls, lighter overall weight and slimmer profile make the A4 series easier to handle, manipulate and deploy in any scenario. Whether for tactical applications, competition shooting or personal defense, the MR A4 series sets the standard for elite-tier AR performance. Backed by a robust aftermarket ecosystem, the MR556 A4 is fully customizable with a wide array of accessories, including rails, handguards and everything needed to create a legally-registered short-barreled rifle (SBR). If you're looking for the ultimate AR platform one that offers exceptional reliability, adaptability and combat-ready durability.

The closest you can get to an actual HK 416 in the United States, offering authentic design and performance
The heavy profile barrel increases rigidity and reduces heat distortion for improved accuracy during extended shooting sessions
M-LOK attachment system is a lightweight, modular platform for secure and customizable accessory mounting
The gas-piston system provides cleaner operation, reduced recoil and improved reliability in adverse conditions
Ambidextrous safety provides intuitive operation and added security

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These items are controlled by the U.S. Government and authorized for export only to the country of ultimate destination for use by the ultimate consignee or end-user(s) herein identified. They may not be resold, transferred, or otherwise disposed of, to any other country or to any person other than the authorized ultimate consignee or end-user(s), either in their original form or after being incorporated into other items, without first obtaining approval from the U.S. government or as otherwise authorized by U.S. law and regulations.

Magazines will be removed from firearms when shipping to states with magazine capacity restrictions.

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WARNING: Handling firearms or firearms parts can expose you to lead and other petroleum products known to the State of California to cause cancer, birth defects, or other reproductive harm. Wash hands thoroughly after handling. For more information go to www.p65warnings.ca.gov (CA Health and Safety Code Section 25249.6).