Home / AR Parts / Heckler and Koch / Heckler and Koch MR556 A4 Upper Receiver/Barrel Assembly 5.56 11 Barrel
Heckler and Koch MR556 A4 Upper Receiver/Barrel Assembly 5.56 11 Barrel

Heckler and Koch MR556 A4 Upper Receiver/Barrel Assembly 5.56 11 Barrel

Lowest Price
MSRP
$2,499
Savings
21% off
In Stock at
6 Stores
Adjustable Gas Regulator for Shooting Suppressed and Unsuppressed
Charging Handle with Dual Claws
Continuous Picatinny Rail Interface Between Upper Receiver and Handguard
Extended, Ambidextrous
M-LOK Interface with Integral Ambi QD Cups
Match Rifle Cold Hammer-forged Barrel
Suppressor-ready Concentric 1/2X28 Threads

Specifications

Caliber
223 Remington
Brand
Heckler and Koch
Model
MR556 A4 Upper Receiver
Series
Upper Receiver Kit
MPN
51000385
UPC
642230270220

Description

Heckler & Koch MR556 A4 11 Upper Receiver Features Optimized for suppressed and CQB applications the 11-inch MR556 A4 upper is built around HK's short-stroke gas piston system with an adjustable gas block enabling smooth function with or without a suppressor. The 1/2x28 threaded barrel is concentric and precision-machined ensuring compatibility with muzzle devices and suppressors. It includes a monolithic M-LOK handguard with integrated ambidextrous QD sling cups a continuous Picatinny rail for optics and sights and an ambidextrous charging handle with dual claw extensions. The match-grade cold hammer-forged barrel provides outstanding accuracy and barrel life while the included bolt carrier group charging handle buffer weight and buffer spring make this upper fully operational out of the box. Heckler & Koch MR556 A4 11 Upper Receiver Specifications Manufacturer: Heckler & Koch (HK) Model: MR556 A4 Upper Receiver Series: MR556 Category: Uppers Caliber: .223 Remington / 5.56 NATO Barrel Length: 11 Thread Pattern: 1/2x28 Firearm Fit: AR-15 Lower Receivers Handguard: M-LOK Interface with Integral Ambi QD Cups Rail: Continuous Picatinny (Upper to Handguard) Charging Handle: Extended Ambidextrous with Dual Claws Barrel Type: Match-Grade Cold Hammer-Forged Gas System: Adjustable Regulator (Suppressed/Unsuppressed) Finish: Anodized Color: Black Includes: Bolt Carrier Group Charging Handle Buffer Weight Buffer Spring
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