HK MR556/416 Small Parts

HKP HK MR556/HK416 FFRS Retaining Spring The retainer spring retains the handguard locking pin on the free floating rail system (FFRS). These can become damaged with the removal of the handguard screws. Once the spring is damaged, they require...

HK 416 & MR556 Gas Block Pin This is the retaining pin for an HK 416 gas block. A must-have, as HK recommends using new pins once they are removed or damaged.  Size: 5 x 18 mm.

HKP Rear Sight Oval Washer HK German oval washer for the rear sight diopter style assemblies. This is the needed washer used in conjunction with the locking washer. Fits and works with all diopter-style rear sights.

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

Magpul M-LOK 3 Slots Rail Section Designed for use with all M-LOK compatible hand guards and forends, M-LOK aluminum rail sections allow the attachment of various 1913 Picatinny spec rail-mounted accessories such as lights, vertical grips, etc. Machined...

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...

H&K MR556/MR762/416/417 Firing Pin Spring This part is great to have on hand as this item is a high wear and replacement part and one of the most common breakage parts on the HK 416/MR556 rifles. Compatible With: HK MR556 HK 416 HK MR762 HK 417 HK...

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

Magpul M-LOK 5 Slot Rail Section Designed for use with all M-LOK compatible Hand Guards and Forends, M-LOK Aluminum Rail Sections allow the attachment of various 1913 Picatinny spec rail-mounted accessories such as lights, vertical grips, etc. Machined...

HKP Gas Piston Ring Replacement Combo Set- 3 Rings The gas rings are prone to periodic breakage and wear and tear and require them to be replaced periodically. These are some of the most common breakage parts we see that need to be replaced on these...

HK MR556 & HK 416 Trigger Guard Retaining Pin Compatible With: HK 416 HK MR556

H&K HK MR556/416 Sling Loop Backplate - Ambidextrous Genuine HK German manufactured 416, MR556 new style backplate with sling loop. Compatible With: HK MR556, HK 416 buffer tubes All Standard AR-15, M4 & M16 buffer tubes

PTR (5.56/.223) & (7.62x51/.308) Muzzle Brake - Threaded 15x1 RH Correct HK threading 15x1 right hand with HK style retaining spring to latch on the HK splined barrel. Made in the US and counts as one US 922r compliant part. Specifications: Threaded...

HK MR556, HK416 & G36, SL8 Gas Piston Ring Replacement Combo Set - 3 Rings This is a high wear common repair & replacement item. The gas rings are prone to periodic breakage & wear, tear and require them to be replaced periodically...

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...

HK416 Full Auto Ambi Selectors Kit - German HK Each set comes complete with everything you will need to upgrade your HK 416 to an ambi selector lever set up. Factory correct German HK and all steel construction. Includes: 2 X selector levers 2 X roll...

H&K HK MR556/MR762/416 Clamping Sleeve Safety Lever There are one of the same pin on both sides. Compatible with: HK MR556 HK 416 HK MR762

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

H&K MR556/MR762/416/G36 (5.56/.223) & (7.62x51/.308) Extractor Spring   A must-have replacement wear part and a great item to have on hand. Compatible With: HK G36 HK G36K HK G36C HK SL8 HK MR556 HK 416 HK MR762

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...

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

HK MR556/MR762/416/HK417 Buffer Retainer Spring This item is the spring for the buffer retainer that is held in the rear of the lower receiver. Compatible With: HK MR556 HK 416 HK MR762 HK 417

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

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 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...

H&K HK MR556/MR762/416 Bolt Catch Pin The factory roll pin is used to hold the bolt catch in place. Great to have on hand in the event this item becomes lost or damaged when doing maintenance Compatible With: HK MR556 HK 416 HK MR762

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. 

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

H&K HK MR556/416 Ejection Port Spring Compatible With: HK MR556 HK 416

AR-15 Ambidextrous Sling End Plate, Universal Made in the USA out of ordnance grade steel. Compatible With: AR15 M5 Other AR buffer tube style builds

H&K HK MR556/416 Firing Pin   New HK German manufactured. This is a great item to have on hand as the firing pin is one of the most abused components in the HK MR556 and HK 416 weapon systems.   Compatible With: HK MR556 HK 416 HK CR556 HK...

H&K HK MR556/416 Battle Grip Storage Cap Pin  

H&K HK MR556/416 Castle Nut For Buffer Tube New HK German manufacture. This buffer tube castle nut will fit both mil-spec and commercial buffer tubes. All steel manufacture. With HK round tool attachment points as well as traditional wrench...

H&K HK MR556/HK416 FFRS Retaining Spring The retainer spring retains the handguard locking pin on the Free Floating Rail System (FFRS). These can become damaged with the removal of the handguard screws. Once the spring is damaged, they have to be...

Nefarious Arms HK G36/SL8/HK 416/MR556 Gas Piston A great spare, upgrade, or replacement part for your HK. Includes 3 piston rings for a complete drop in replacement part. TiN coated gold for added protection and an overall great part.  Compatible...

H&K HK MR556/762/416/417 Bolt Catch Spring Compatible With: HK MR556 HK 416 HK MR762 HK 417

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 Pin Compatible With: HK MR556 HK 416 HK MR762

HKP AR Grip Screw 1/4x28x1 Hex w/ Locking Washer This replacement screw is to mount your AR-15/AR-10 pistol grip. 1/4x28x1 with a star lock washer. The best option to use for new builds or to replace your worn out or stripped screw. Black oxide finish...