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MR556 Upper Receiver Kit
SKU#81000077

$1,999.00

The MR556A1 Upper Receiver Kit includes a complete upper receiver/barrel assembly, bolt carrier assembly, buffer, and buffer spring allowing most high-quality 5.56 mm AR-style rifles to be retrofitted to HK’s pusher rod system.

  • Complete MR556 Upper Receiver/Barrel Assembly— HK 16.5 inch cold-hammer forged barrel, upper receiver with forward assist, extended convertible charging handle, HK Free Floating Rail System handguard
  • Complete MR556 Bolt Group Assembly
  • Tungsten Filled HK Proprietary Buffer
  • HK Proprietary Buffer (Action) Spring
  • NOTE: The MR556A1 Upper Receiver Kit is not classified as a firearm and can be purchased without a Federal Firearms License ( FFL).

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