Receivers / Flats / Uppers

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
  • New - HKP SP5K 9mm Drop In Paddle Mag Release Upgrade Kit - HKP-18192 HKP SP5K 9mm Drop In Paddle Mag Release Upgrade Kit
    Add to Cart

    HKP SP5K 9mm Drop In Paddle Mag Release Upgrade Kit

    HKP HK Parts

    $74.95
    HK SP5K Anti-Rattle Roller Tipped "Paddle" Magazine Release Install Kit No modifications, no refinishing...complete drop-in kit included. New USA made busing for a drop-in install kit for the HK SP5K. This kit will allow any end-user to quickly,...
    $74.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $74.95
    Subtotal:
  • New - HKP 90 Series Paddle Mag Release Easy Install Fixture - HKP-17587 HK 90 Series Paddle Mag Release Easy Install Fixture
    Add to Cart

    HK 90 Series Paddle Mag Release Easy Install Fixture

    HKP HK Parts

    $187.95
    HKP 90 Series Paddle Mag Release Easy Install Fixture The original one and only paddle mag release fixture. The perfect jig for the installation of the factory correct paddle mag release with the proper hole placement and an easy to use jig that will...
    $187.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $187.95
    Subtotal:
  • Out Of Stock
    New - H&K Barrel Retaining Pin - 5.15mm - HKP-01662 HK Barrel Retaining Pin - 5.15mm

    HK Barrel Retaining Pin - 5.15mm

    H&K Heckler & Koch

    $14.95
    H&K Barrel Retaining Pin - 5.15mm This is the barrel pin used for installing a new or replacement barrel. HK suggests using a new factory barrel pin when installing or reinstalling an HK barrel in the trunnion. Each pin is slightly oversized for...
    $14.95
    Out Of Stock
    Qty in Cart: 0
    Quantity:
    Price:
    $14.95
    Subtotal:
  • New - H&K HK MR556/MR762/416/417 Rear Lower Receiver Locking Pin - HKP-02672
    Add to Cart

    HK416, HK417, MR556, MR762 Rear Lower Receiver Locking Pin

    H&K Heckler & Koch

    $79.95
    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...
    $79.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $79.95
    Subtotal:
  • Out Of Stock
    New - RCM HK G3, HK 91, PTR Trunnion - HKP-01289 RCM HK91, G3, PTR Trunnion

    RCM HK91, G3, PTR Trunnion

    RCM

    $64.95
    RCM Trunnion For The HK91/G3 Series - US Made This part is machined from ordnance grade 9310 enhanced steel and heat treated to exact HK specifications. This item is the best USA-made trunnion on the market. Machined to spec and are to the custom ground...
    $64.95
    Out Of Stock
    Qty in Cart: 0
    Quantity:
    Price:
    $64.95
    Subtotal:
  • On Sale
    New - HKP MP5 Flat Brim Snapback Hat - OSFM - HKP-21451-M HK MP5 Hat - Snapback - Flat Brim - OSFM
    Choose Options

    HK MP5 Hat - Snapback - Flat Brim - OSFM

    HKP HK Parts

    Now: $17.95
    Was: $22.99
    HKP MP5 Flat Brim Snapback Hat - OSFM Get your hands on some of our premium hats!  Features: Official HKP merchandise 5" wide HKP logo Cotton twill Mesh back panels Plastic adjustable snap closure Size: OSFM Six-panel
    Now: $17.95
    Was: $22.99
    Choose Options
    Qty in Cart: 0
    Quantity:
    Price:
    Now: $17.95
    Was: $22.99
    Subtotal:
  • New - H&K MP5, HK94 Case Deflector Rivet - HKP-00147 HK MP5, HK94 Case Deflector Rivet
    Add to Cart

    HK MP5, HK94 Case Deflector Rivet

    H&K Heckler & Koch

    $9.95
    H&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...
    $9.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $9.95
    Subtotal:
  • New - Lazy Wolf VP Series F2 Flat Face Trigger - Red Tab - HKP-19290 Lazy Wolf VP Series F2 Flat Face Trigger - Red Tab
    Add to Cart

    Lazy Wolf VP Series F2 Flat Face Trigger - Red Tab

    Lazy Wolf

    $134.95
    Lazy Wolf VP Series F2 Flat Face Trigger - Red Tab In a collaboration with Lazy Wolf Guns, HK Parts is offering the finest aftermarket triggers for your HK VP9 & VP40 handguns. The drop in VP9 series trigger is the best trigger ever developed after...
    $134.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $134.95
    Subtotal:
  • New - H&K HK416 A5 Factory German Extended Castle Nut - HKP-19164
    Add to Cart

    HK416A5 Factory German Extended Castle Nut

    H&K Heckler & Koch

    $75.95
    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. 
    $75.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $75.95
    Subtotal:
  • New - H&K HK MR556 Receiver Take Down Tool - HKP-02653
    Add to Cart

    HK MR556 Receiver Take Down Tool

    H&K Heckler & Koch

    $19.95
    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...
    $19.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $19.95
    Subtotal:
  • New - H&K HK MR556/MR762/416/417 Detent Takedown Pin - HKP-02540
    Add to Cart

    HK416, HK417, MR556, MR762 Detent Takedown Pin

    H&K Heckler & Koch

    $9.95
    H&K HK MR556/MR762/416/417 Detent Takedown Pin Compatible With: HK MR556 HK 416 HK MR762 HK 417
    $9.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $9.95
    Subtotal:
  • New - HK G36/SL8 (5.56/.223) Factory Recoil Buffer - HKP-18541
    Add to Cart

    HK G36/SL8 (5.56/.223) Factory Recoil Buffer

    USA

    $16.95
    HK 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 Clones
    $16.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $16.95
    Subtotal:
  • Total: items /

Adding your products to cart