HK MR556/416 Receivers / Uppers

Enhanced HK German MR556 & 416 Buffer Spring The HK MR556/416 buffer spring will also work with other AR-15 and M-16 rifles. It is a high-wear item and a must-have replacement part. Compatible With: HK MR556 HK416 HK416 A5 HK M27 AR15, M4 & M16

HK German HK 416, MR556 Ejection Port Cover In RAL 8000 HK manufactured newer polymer style cover assembly found on the latest HK 416 & MR556's. This item can also be used on other AR15 style projects to enhance the build with the finest ejection...

HK German Enhanced ambi 416 Bolt Release - HK 416 A5 The real deal HK German HK416A5 bolt release. Made from hardened steel.

Mil-Spec US Made Buffer Tube Compatible With: HK MR556 & 416 All AR-15 style platforms Features: Made From T7 7075 Aircraft grade aluminum 6 Position Made in the USA Each features a highly polished inside tube Black Mil-spec triple hard coat...

H&K HK MR556/416 Ejection Port Cover - Black HK manufactured newer polymer style cover assembly found on the latest HK 416 & MR556. This item can also be used on other AR15-style projects to enhance the project with the finest ejection port cover...

H&K HK MR556/MR762/416 Buffer Retainer Pin Compatible With: HK MR556 HK 416

H&K HK MR556/MR762/416/417 Buffer Retaining Pin New HK German proprietary HK designed buffer pin unique to the HK 416 and MR 556 series.  Compatible With: HK MR556 HK 416 HK MR762 HK M27

H&K HK MR556/MR762/416/417 Takedown Pin Detent Spring New HK German manufacture. Detent spring for the rear takedown pin. Compatible With: HK MR556 HK 416 HK MR762 HK 417

H&K HK MR556/MR762/416/417 Rear Lower Receiver Locking Pin This is the rear takedown pin with ball detent and locking mechanism installed. The idea behind this type of system is to decrease the movement of the upper and lower receivers and improve...

H&K HK MR556/MR762/416/417 Detent Takedown Pin Compatible With: HK MR556 HK 416 HK MR762 HK 417

Ergo AR-15 Castle Nut For Buffer Tubes - US Made Steel Castle-nut for AR buffer tubes fits both mil-spec and commercial buffer tubes alike.  Compatible With: HK MR556 & 416 AR-15 style platforms

H&K HK MR556 Receiver Take Down Tool This part is the tool used to tighten down the stock movement on the E1/E2 stock. Each tool will be stored in the rear of the E1/E2 stock. Compatible With: HK MR556 Please Note: We get...

HK German HK 416, MR556 Ejection Port Cover Door Assembly Complete This is the newer polymer style cover found on the latest HK 416 and MR556's. This is the complete ejection port door assembly needed on all AR15 or MR556/HK416 models. Can also be used...

H&K HK416 A5 Factory German Extended Castle Nut Original HK Factory German steel 416 A5 Extended Castle Nut. Perfect for MR556, HK 416 A5 builds, or upgrades. 

HK 416, MR556 End Plate For Receiver & Buffer Tube New HK German manufacture. Compatible With: HK MR556 & HK 416 upper receiver/buffer tubes

HK MR556 & HK416 Buffer Tube Wrench The perfect metric wrench to remove and install the MR556 & HK 416 castle nuts on the buffer tube. A perfect addition to have on hand for OTB or other HK buffer tube upgrades, etc. Made from all steel, heat...

H&K HK MR556 Front Lower Receiver Locking Pin With Spring Loaded Detent This part is the front (large) takedown pin with ball detent and locking mechanism installed. The idea behind this type of system is to decrease the movement of the upper and...

H&K HK MR556/MR762/416 Forward Assist Pin Compatible With: HK MR556 HK 416 HK MR762

HK German Stripped HK MR556 Upper Receiver New factory German incomplete and unmarked MR556 upper receiver. Compatible With: HK MR556 HK MR223 HK 416 Do you need a matching lower for your build?  STS416 A5 LOWER - Specialized Tactical...

HK MR556 & 416 Upper Receiver Threaded Piston Guide Compatible With: HK MR556 HK 416 HK M27

Ejection Port Axle - Steel- HK 416 New HK USA manufacture for the HK 416 family of firearms. This is the axle that holds the ejection port cover in place on the upper receiver. 

H&K HK MR556/MR762/416 Forward Assist Assembly H&K Germany factory MR556 & HK416 forward assist assembly complete. Compatible With: HK MR556 HK 416 HK MR762

New HK Factory German MR556 Upper Kit with M-LOK forearm Includes: Complete MR556 upper receiver with M-LOK forearm MR556 Bolt group Complete Tungsten Filled HK Buffer HK Buffer Spring One 30 Round HK Steel Maritime Magazine No FFL required as the...

H&K HK MR556/MR762/416/417 Forward Assist Plunger Spring New HK German manufacture. Compatible With: HK MR556 HK 416 HK MR762 HK 417 HK G28 HK M27

HK MR556 & 416 Ejector Port Cover Pin Compatible With: HK MR556 HK 416

HKP 416 10.4" 5.56 Complete Upper Kit Complete Each kit includes the complete upper assembly, bolt group, tungsten buffer, & high-reliability SS recoil spring. This upper kit is a complete gas piston HK 416 style upper assembly that will drop on your...

HK 416A5 - Stripped Upper Receiver - Black This is the factory correct receiver for a true 416 build as it features the M16 relief cut in the bottom, rear portion of the receiver (shown in last pricture). Compatible With: HK 416 HK MR223 HK MR556 Need...

HKP HK 416 11.5" 5.56 Complete Upper Kit Complete HKP 416 style complete upper assembly. This top-tier assembly seamlessly fits onto your mil-spec lower or a STS 416 lower, providing the perfect solution for those seeking an 11.5" 416 style upper without...

HK416C Complete Upper Kit - 9"  After years trying to get these back in. We finally bring you a rare unicorn of a find. With our complete 416c upper kit all that would be needed to complete this kit would be a mil-spec lower or a STS 416c lower...

H&K HK 416/417/MR556/MR762 Bridge For Lowers Compatible With: HK MR556 HK 416 HK MR762 HK 417

H&K HK MR556/416 Forward Assist Plunger Pin  

New HK German Partially Pre-Assembled MR556/MR223 Upper Receiver Each unit comes just as shown with the F/A (forward assist) assembly and ejection port door assembly installed from the HK factory.  Compatible With: HK MR556 HK MR223 HK...

AR-15 Commercial Buffer Tube Compatible With: HK MR556 & 416 All AR-15 style platforms Features: Made From T7 7075 Aircraft grade aluminum Made in the USA 6 Position Each features a highly polished inside tube Black Mil-spec triple hard coat...

HK German Un-Assembled Stripped HK 416A5 Upper Receiver - RAL 8K Brand new factory German RAL 8000 416A5 upper receiver. Compatible With: HK MR556 HK MR223 HK 416 Looking for a matching lower for your build?  STS416 A5 LOWER - Specialized Tactical...

US Made Complete HK 416, MR556 Style Upper Receiver New US made HK416/MR556 style upper receiver.  Includes: Upper receiver Forward assist assembly Ejection port door assembly Piston guide Compatible With: HK MR556 HK MR223 HK 416 Need a...

AR-15 Commercial Buffer Tube Kit Compatible With: HK MR556 & 416  All AR-15 style platforms  Includes: Made with T7 7075 aircraft-grade aluminum Made in the USA with a polished inside tube Mil-Spec triple hard coat Teflon anodized...

H&K HK 416 & HK MR556 Assembly Wrench Tool Factory HK German multi-tool for the HK416 and MR556. The perfect tool for a complete breakdown. 

HKP HK 416 A1/A3, MR556 Upper Receiver Forging HK Parts' very own 416 upper receiver forging. This is the first time that these forgings have been made available to the public. Our receivers come with the ever popular Cerro Forge "keyhole" marking. Cerro...

HK German Un-Assembled/Stripped HK MR556/MR223 A5 Upper Receiver Factory HK MR556 A5 upper receiver.  This is the semi-auto MR556 variant. Compatible With: HK MR556 HK MR223 HK 416*** Need a matching lower for your build?  STS416 A5 LOWER -...

HK 416, MR556 & MR762, HK 417 - Buffer Staking Tool - German HK Rare HK factory HK staking tool for the castle nut to be staked. These took over 3 years to get and offered for cost while supplies last! Each tool is the factory correct tool used for...