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Upper Conversion Kit - HK MR556 & HK 416 14.5" 556

SKU: HKP-17877

MR556 & HK416 Upper Conversion Kit - 14.5"


Finally an answer for all of those that have been wanting a 14.5" 416 or MR556 upper or a barrel option for your MR556, CR556 & HK 416's. Each upgrade kit is as close as you can get for those that want an HK 416 style upper upgrade but without the excessive price tag of a factory HK 416 upper kit. This is the finest offering ever available here in the USA. Works on any HK 416 or MR556 upper receiver. Each unit is test fitted on HK416 & MR556 uppers for accuracy and compatibility. Works with all HK spec uppers & forearms.


Each US made conversion kit includes:

  • Proven Gas Piston Design
  • 14.5" 416R Stainless 1/7 twist 5.56 fully "Nitrided" barrel
  • Muzzle end threaded 1/2 X 28
  • Enhanced Stainless steel barrel nut
  • Newer updated 416 style stainless steel billeted "vented" gas block
  • Full machined bayonet lug & ambi sling loops on gas block
  • A2 416 style flash hider & crush washer
  • Barrel nut install & removal tool for ease in making the barrel swap a breeze


Each conversion kit includes all the necessary parts you need for the barrel conversion to your HK 416 or MR556. Simply add your gas piston assembly, upper receiver & bolt carrier group. Why spend needless thousands of dollars on used PD trade in 416 uppers or imperfect cut down MR556 conversions when you can have the closest thing for a fraction of the price. 100% USA made!

No FFL required as the upper assembly is only considered parts and not an FFL item.


*Should not be used with a suppressor, unless it is a zero pressure suppressor*

Condition: New
Origin: USA
Price: $699.95
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Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
Upper Conversion Kit - HK MR556 & HK 416 14.5" 556
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