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
  • Out Of Stock
    New - HKP Rear Stock Pin Bushing Weldment - HKP-17573

    HK Stock Pin Bushing Weldment

    HKP HK Parts

    $3.95
    HK Stock Push Pin Bushing Weldment All-steel stock pin bushing weldment for welding in the rear of the flat. This bushing welds into the folded flat and guides the large push pin through the receiver to hold the stock to the receiver. Compatible...
    $3.95
    Out Of Stock
    Qty in Cart: 0
    Quantity:
    Price:
    $3.95
    Subtotal:
  • New - HKP MP5, HK94 Case Deflector Rivet - HKP-18008
    Add to Cart

    HK MP5, HK94 Case Deflector Rivet - US

    HKP HK Parts

    $1.95
    HKP MP5, HK94 Case Deflector Rivet Each case deflector will require 2 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. These are a factory correct rivet that...
    $1.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $1.95
    Subtotal:
  • New - PTR HK 91/G3 (7.62x51/.308) Receiver Flat - HKP-02320 HK91, G3 Receiver Flat - US Made
    Add to Cart

    HK91, G3 Receiver Flat - US Made

    PTR

    $99.95
    HK G3, 91, PTR & CETME Flat - PTR Made by PTR with original HK tooling using factory specifications and a properly stamped receiver. No FFL is required as this is an unfolded flat that ships directly to the customer. This US made receiver flat...
    $99.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $99.95
    Subtotal:
  • New - PTR HK 91/G3/51 (7.62x51/.308) Flat With Weldment Set - HKP-02086 HK91, G3 Flat with Weldment Set
    Add to Cart

    HK91, G3 Flat with Weldment Set

    PTR

    $166.95
    HK91, G3, PTR, CETME Flat & Weldment Combo - PTR Made by PTR91 on original HK tooling using factory specifications and a properly stamped receiver ready to roll and build. No FFL transfer is required as this is an un-folded flat.  Compatible...
    $166.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $166.95
    Subtotal:
  • New - HKP Semi Shelf Weldment - Metal Grip Housing - HKP-16657 HK Semi Shelf Weldment - Metal Grip Housing
    Add to Cart

    HK Semi Shelf Weldment - Metal Grip Housing

    HKP HK Parts

    $14.95
    HKP Semi Shelf Weldment Metal Grip Housing For Semi-Auto Trigger Packs This HK German specification metal trigger frame weldment is designed for converting SEF style housings from full auto to semi-auto. This weldable block or shelf is essential for...
    $14.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $14.95
    Subtotal:
  • New - Semi Auto Shelf For Receiver - Billeted - HKP-01521
    Add to Cart

    Semi Auto Shelf For Receiver - Billeted

    $19.95
    Semi Auto Shelf For Receiver - Billeted HK Semi Auto Shelf milled from one solid billet to HK's factory specifications (no castings here). This is the needed receiver shelf that is welded to the receiver to allow the use of the clipped & pinned...
    $19.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $19.95
    Subtotal:
  • New - HKP Picatinny Rail For HK Receivers - 17 Slot - HKP-01446 HK Picatinny Rail For HK Receivers - 17 Slot
    Add to Cart

    HK Picatinny Rail For HK Receivers - 17 Slot

    HKP HK Parts

    $69.95
    HKP Picatinny Rail For HK Receivers - 17 Slot Mil-Spec all steel Picatinny rail in the white. Relief cut for HK receivers and made for mounting scopes and optics to HK builds. This unit easily welds to the top of your HK receiver. Compatible With: HK...
    $69.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $69.95
    Subtotal:
  • New - HKP Semi Auto Shelf for Receiver - Billeted - HKP-21470 HK Semi Auto Shelf for Receiver - Billeted
    Add to Cart

    HK Semi Auto Shelf for Receiver - Billeted

    HKP HK Parts

    $17.95
    HKP Semi Auto Shelf for Receiver - Billeted HK Semi Auto Shelf, Hanger Block to HK's factory specifications for c/p trigger housings. Weld on shelf that is the needed receiver block that welds to the rearward portion of the magwell to allow the use of...
    $17.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $17.95
    Subtotal:
  • On Sale
    New - HKP Flat Bending Billeted Jig Set For All HK Style Flats - HKP-19583 HK Style Jig Set - Flat Bending - Billeted
    Add to Cart

    HK Style Jig Set - Flat Bending - Billeted

    HKP HK Parts

    Now: $399.95
    Was: $449.95
    Flat Bending Jig Set For All HK Style Flats - Billeted - Aluminum Aluminum billeted universal flat bending jig for all HK receiver flats including PTR .308 flats and the PTR/LSC flats. Each bending jig comes complete with all the pieces you need for...
    Now: $399.95
    Was: $449.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    Now: $399.95
    Was: $449.95
    Subtotal:
  • New - LSC MP5 9mm Receiver Flat - HKP-20555 LSC MP5 9mm Receiver Flat
    Add to Cart

    LSC MP5 9mm Receiver Flat

    LSC

    $199.95
    MP5 Receiver Flat - LSC LSC HK MP5 receiver flat is the most in spec flat that has ever been available. The best option for your HK German parts kit build. This flat is considered by many to be most sought after HK flat available on the market and...
    $199.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $199.95
    Subtotal:
  • New - HKP HK 416/MR556 A5 Style Castle Nut-Extended - HKP-18058
    Add to Cart

    HK 416, R556 Castle Nut - A5 Style - Extended

    HKP HK Parts

    $39.95
    HK 416, MR556 A5 Style Extended Length Castle Nut Unlike the factory German A5 castle, our A5 extended buffer tube castle nut is compatible with both mil-spec & commercial buffer tubes.  Crafted from ordnance grade steel and nitrided for a...
    $39.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $39.95
    Subtotal:
  • New - HKP Picatinny Rail For HK Receivers - 15 Slot - HKP-18241 HK Picatinny Rail For HK Receivers - 15 Slot
    Add to Cart

    HK Picatinny Rail For HK Receivers - 15 Slot

    HKP HK Parts

    $59.95
    HKP Picatinny Rail For HK Receivers - 15 Slot Mil-Spec all steel CNC'ed picatinny rail in the white, relief cut to fit flush and low profile on HK receivers. The most solid and consistent mounting platform made for mounting scopes and optics to HK builds...
    $59.95
    Add to Cart
    Qty in Cart: 0
    Quantity:
    Price:
    $59.95
    Subtotal:
  • Total: items /

Adding your products to cart