HK MR556 HKey Forearm Upper Kit

(1 customer review)


New HK Factory German MR556 Upper Kit With Key Mod Rail

Only a few available latest HK production.

HK MR556 Upper kit includes:

  • Complete MR556 upper receiver with HKey forearm and 2 rail segments
  • MR556 Bolt group Complete
  • Tungsten Filled HK Buffer
  • HK Buffer Spring
  • One 30 Round HK Steel Maritime Magazine

This unit will drop on any mil-spec AR-15 lower receiver.

No FFL required as the upper assembly is only considered a part and not an FFL item. This is a rare offering and extremely hard to find new.

  • Condition: New
  • Origin: German
  • Brand: Heckler & Koch
  • Caliber: 5.56 x 45mm / .223

Out of stock

Join the waitlist to be emailed when this product becomes available

SKU: HKP-17366

Share your thoughts!

5 out of 5 stars

1 review

Let us know what you think...

One review with a 5-star rating

  1. AndrewB

    Long time to review it sorry.

    AndrewB (verified owner)

    I love it. 560 rounds no jams. Finally got Geissele SSA and SMR parts and an ACOG. We shot dime sized groups out at 50 meters with mk262. Get this… With a HOT barrel 160 rounds later. It was still doing 2-3” groups at 202 yards. Please stock more soon.

    (0) (0)

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