Manufacturer: HK
Model/Series: MR556 A4
Caliber: 5.56x45mm
Action: Semi-Auto
Operating System: Gas Piston
Barrel Length: 11 inches
Barrel Twist Rate: 1:7
Barrel Material: Steel
Barrel Finish: Black
Barrel Description: Threaded
Thread Pattern: 5/8"x24
Capacity: 10
Receiver Description: Picatinny Rail
Receiver Finish: Patriot Brown
Handguards: M-LOK
Grips: Black Polymer
Sights: None
Trigger Pull Weight: 4.50–5.60 lbs
Safety: Ambidextrous Safety Lever
Overall Length: 26.5 inches
Height: 7.5 inches
Width: 3.07 inches
Weight: 6.61 lbs
Hand: Ambidextrous

Features

The MR556 A4 short-stroke gas piston operating system does not impart hot carbon fouling back into the action, allowing the weapon to run longer, with less maintenance and with less wear on internal components. Its adjustable gas regulator allows the operator to tune the action specifically for suppressed or unsuppressed operation. Fully ambidextrous controls, lighter weight and a slimmer profile make the new A4 easier to operate, manipulate and employ.

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All NFA Rules Apply

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.

California 10+ Round Magazine Buyers: PSA values your freedom and constitutional rights above all else. However, PSA will not accept new orders nor will ship any order until the Ninth Circuit Federal Court of Appeals mandate becomes finalized. Once this mandate is finalized, we will start accepting new orders and ship 10+ round magazines to California Customers.

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).