Receivers / Flats / Uppers
Explore our premier selection of HK receivers, flats, and uppers at HKParts, perfect for building or upgrading your Heckler & Koch firearms. Our products feature precision-engineered MP5 receiver flats, HK 416 complete upper assemblies, and a wide range of custom options designed for tactical and precision shooting. Whether you are customizing an MP5, upgrading an HK416, or constructing a new firearm, our high-quality components provide unparalleled reliability and performance.
- Product
- Qty in Cart
- Quantity
- Price
- Subtotal
-
On Sale
HK416, MR556, AR-15 Buffer Tube Castle Nut
USA
Now: $7.95Was: $9.99AR-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: HK416, MR556 AR-15 style platformsHKP-02729Now: $7.95Was: $9.99 -
Out Of Stock
HK416 E1, MR556 Charging Handle - Ambidextrous
H&K Heckler & Koch
$129.95H&K HK MR556/416 E1 Charging Handle - Ambidextrous HK's design boasts a smooth & easy to release latch with an enhanced oversized charging handle. Compatible With: HK MR556 HK 416 Other AR15, M4 & M16 applicationsHKP-01959$129.95 -
HK MP5, MP5K Magazine Release Paddle - Anti-Rattle Roller-Tip - 9mm
H&K Heckler & Koch
$64.95Heckler and Koch Anti-Rattle Roller Tipped "Paddle" Magazine Release for HK MP5, MP5K Factory German made Paddle mag release for all 9mm MP5, MP5K HK builds. Our parts are made by HK in Germany and are factory-fresh production. Compatible With: MP5,...HKP-00117$64.95 -
HK MP5, HK94 Case Deflector Rivet
H&K Heckler & Koch
$9.95H&K MP5, HK94 Case Deflector Rivet Each case deflector, US or German-made, will require two rivets to attach the case deflector to the receiver or flat. If you want the factory look and feel of doing it right, these rivets are a must-have. These are...HKP-00147$9.95 -
HK MR556 Receiver Take Down Tool
H&K Heckler & Koch
$19.95H&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...HKP-02653$19.95 -
On Sale
HK G36, SL8 Recoil Buffer - Factory - US
USA
Now: $12.95Was: $16.95HK G36 Or SL8 Factory Recoil Buffer A must have spare part as the buffer is prone to wear and breakage. Compatible With: All HK G36 models SL8 models ClonesHKP-18541Now: $12.95Was: $16.95 -
HK MP5, MP5K Magazine Release Set
H&K Heckler & Koch
$184.95Heckler and Koch Magazine Release Set for HK MP5 and HK MP5K This is the complete magazine release kit that includes both the paddle mag release and standard left-to-right mag release on your HK 9mm rifle or pistol build. Set...HKP-02402$184.95 -
HK416, MR556 Buffer Tube Castle Nut
H&K Heckler & Koch
$34.95Heckler and Koch Castle Nut for Buffer Tube for HK416 and HK MR556 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...HKP-15230$34.95 -
On Sale
HK33, HK53, HK93 Receiver Flat - Complete Weldment Set
HKP HK Parts
Now: $183.95Was: $229.95HK .223, 556, & 300 BLK Receiver Flat With Complete Weldment Set Combo Each flat and weldment set comes with 223/556/300BLK complete as a builders combo ready to assemble. Compatible With: HK93, HK33, & HK53 Style Builds 300...HKP-00006Now: $183.95Was: $229.95 -
On Sale
HK MP5 Receiver Flat - .40 S&W, 10mm
HKP HK Parts
Now: $194.95Was: $399.95MP5 40 & MP5 10mm Receiver Flat - USA The new and latest production with the weldment locations is already lasered and ready to go. This flat is the finest available for the MP5 40/10 family of firearms. Compatible With: MP5 .40 Cal MP5 10mm MP5 ...HKP-00767Now: $194.95Was: $399.95 -
On Sale
HK MP5, HK90 Series Paddle Mag Release Bushing - Full Auto
MKE
Now: $1.95Was: $2.59MKE Magazine Release Bushing for HK MP5, MP5K and HK90 Firearms This part is for use in all HK90-series Heckler and Koch weapon systems and is used for installing a paddle mag release. This is not for use on semi-auto HK builds. This part is intended for...HKP-22283Now: $1.95Was: $2.59 -
On Sale
HK416, MR556 Buffer Tube Wrench
HKP HK Parts
Now: $23.95Was: $29.95HK 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...HKP-17124Now: $23.95Was: $29.95