MR556 A4 5.56 16.5 30+1 GRY

HK MR556 A4 Features
The MR556 A4’s short-stroke gas piston operating system reduces heat and carbon in the receiver for improved long-term reliability and cooler running under sustained fire. Paired with an HK416 upper and a 16.5" barrel threaded 1/2x28 for muzzle devices, the platform offers excellent durability and straightforward integration of brakes or suppressors while maintaining factory-level accuracy and lockup.

Ergonomics focus on user adaptability and control: a collapsible / folding stock with HK416 slimline furniture, M-LOK handguard for modular accessory mounting, a fully ambidextrous lower and ambidextrous safety lever, and a 30-round magazine configuration to support a wide range of roles. The rifle ships with one 30 rd magazine and a gray Cerakote finish that resists corrosion and reduces glare.

HK MR556 A4 Specifications
Manufacturer: Heckler & Koch (HK USA)
Model: MR556 A4
Family: MR556 Series
Category: Rifles / AR Style Centerfire Rifles
Action: Semi-Auto (Short-stroke gas piston)
Caliber: .223 Rem / 5.56 NATO
Barrel Length: 16.5 inches
Barrel Description: Chrome-lined (threaded 1/2x28)
Rate of Twist: 1-in-7"
Thread Pattern: 1/2x28
Finish: Gray Cerakote (applied finish)
Receiver: HK416 upper; fully ambidextrous lower
Stock: Collapsible / Folding Stock
Stock / Furniture: HK416 Slimline Furniture
Handguard: M-LOK handguard
Capacity: 30 + 1
Included Magazines: 1 × 30 rd
Sights: None (optic cut / optic-ready not specified)
Weight: 7.67 lbs
Overall Length: 33.25" to 36.5" (stock collapsed/extended)
Number of Magazines: 1
Special Features: Threaded barrel; short-stroke gas piston; HK416 upper receiver; M-LOK handguard; fully ambidextrous controls; ambidextrous safety lever
Shipping Weight: 14.4 lbs.

More Information
Barrel Length 16.5
Caliber 5.56
Capacity 30
Condition New in Box
Finish Per Color Grey
Manufacturer Heckler and Koch
Manufacturer Part Number 81001308
Model MR556 A4
Type Modern Sporting Rifles
UPC 642230271982