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.

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  • HK MP5, HK94 Rivet for  Sling  clip - Pack of 3 HK MP5, HK94 Rivet for  Sling  clip - Pack of 3

    HK MP5, HK94 Rivet for Sling clip - Pack of 3

    LSC

    $3.95
    LSC HK MP5, HK94 Rivet for Sling Clip and Case Deflector - Pack of 3 Each sling clip, US or German-made, will require 3 rivets to attach to the receiver or flat.  Compatible With:
    HKP-99400
    $3.95
    Qty in Cart: 0
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    $3.95
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  • HK G3 Complete Parkerized Rear Receiver Section - SURPLUS FMP HK CONTRACT HKP-22375 HK G3 Complete Parkerized Rear Receiver Section - SURPLUS FMP HK CONTRACT HKP-22375

    HK FMP G3 Rear Receiver Section - SURPLUS

    FMP HK CONTRACT

    $24.95
    H&K G3 Complete Parkerized Rear Receiver Section without Rear Sight - SURPLUS UNIT CONDITION WILL VARY  Steel rear receiver section manufactured by FMP on HK tooling. Does not include the rear sight...
    HKP-22375
    $24.95
    Qty in Cart: 0
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    $24.95
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  • HK CC9 Magazine Spring - 12 Round

    HK CC9 Magazine Spring - 12 Round

    H&K Heckler & Koch

    $9.95
    Heckler and Koch 12-Round Magazine Spring for HK CC9 Genuine 12-round HK CC9 steel magazine spring. Compatible With:
    HKP-22509
    $9.95
    Qty in Cart: 0
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    $9.95
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  • New - H&K MR556/416 E2 Charging Handle - HKP-22021 HK416, MR556 Charging Handle - E2

    HK416, MR556 Charging Handle - E2

    H&K Heckler & Koch

    $153.95
    Heckler and Koch E2 Charging Handle for HK416, MR556 Factory HK charging handles for the MR556, HK416 platform. The standard MR556 charging handle allows the release latch to be configured on either...
    HKP-22021
    $153.95
    Qty in Cart: 0
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    $153.95
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  • New - H&K MR762 A4/417 Magazine Catch - HKP-21961 HK417, MR762A4 Magazine Catch

    HK417, MR762A4 Magazine Catch

    H&K Heckler & Koch

    $99.95
    Heckler and Koch Magazine Catch for HK417 and HK MR762 German-made magazine catch for HK MR762 A4 and HK417.
    HKP-21961
    $99.95
    Qty in Cart: 0
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    $99.95
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  • Out Of Stock
    New - H&K HK G36, HK SL8 Roll Pin for Gas Piston - Black - HKP-16386

    HK G36, SL8 Roll Pin - Gas Piston

    H&K Heckler & Koch

    $9.95
    H&K HK G36, HK SL8 Roll Pin for Gas Piston
    HKP-16386
    $9.95
    Qty in Cart: 0
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    $9.95
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  • New - H&K HK MR762/417 Charging Handle Catch - HKP-16852 HK417, MR762 Charging Handle Catch

    HK417, MR762 Charging Handle Catch

    H&K Heckler & Koch

    $59.95
    Heckler and Koch Extended Charging Handle Catch Complete for HK MR762, HK417  New HK German manufacture. A great part to have on hand as these are prone to breakage and wear. Compatible With:
    HKP-16852
    $59.95
    Qty in Cart: 0
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    $59.95
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  • New - H&K MR762 A4 Complete Charging Handle - HKP-21967 HK MR762 A4 Charging Handle

    HK MR762 A4 Charging Handle

    H&K Heckler & Koch

    $199.95
    H&K MR762 A4 Charging Handle Upgrade your MR762 or HK417 style rifle with this factory H&K ambidextrous charging handle, engineered for smooth, reliable operation from either side. Built to Heckler &...
    HKP-21967
    $199.95
    Qty in Cart: 0
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    $199.95
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  • On Sale
    New - HKP HK MP5 9mm Receiver Flat w/o Sling Clip - HKP-21828 HK MP5 Receiver Flat - 9mm - no Sling Clip

    HK MP5 Receiver Flat - 9mm - no Sling Clip

    HKP HK Parts

    Now: $121.09
    Was: $189.95
    HKP HK MP5 9mm Receiver Flat w/o Sling Clip The MP5 9mm receiver flat serves as the foundation for custom MP5 builds. This version does not include a sling clip cutout, offering flexibility for...
    HKP-21828
    Now: $121.09
    Was: $189.95
    Qty in Cart: 0
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    Now: $121.09
    Was: $189.95
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  • HK21E Feed Mechanism, Complete - 7.62 / .308 HK21E Feed Mechanism, Complete - 7.62 / .308

    HK21E Feed Mechanism, Complete - 7.62 / .308

    H&K Heckler & Koch

    $22,495.95
    HK21E Feed Mechanism Complete - German HK - DM1 Links New genuine HK date-coded and marked 21E complete feed mechanism. These are the last of the genuine feed mechs available and due to the HK...
    HKP-00584
    $22,495.95
    Qty in Cart: 0
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    $22,495.95
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  • New - H&K HK MR762/417 Enhanced Buffer Tube - Black - HKP-16770 HK417,  MR762 Enhanced Buffer Tube

    HK417, MR762 Enhanced Buffer Tube

    H&K Heckler & Koch

    $176.95
    H&K HK MR762/417 Enhanced Buffer Tube/Receiver Extension - Black Brand new factory HK German manufactured MR762, MR308, & HK 417 buffer tube. Compatible With: HK MR762
    HKP-16770
    $176.95
    Qty in Cart: 0
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    $176.95
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  • HK MP5 Case Deflector - 9mm, .40 S&W Receivers HK MP5 Case Deflector - 9mm, .40 S&W Receivers

    HK MP5 Case Deflector - 9mm, .40 S&W Receivers

    HKP HK Parts

    $24.95
    HKP HK MP5 Case Deflector - 9mm, .40 Receivers US-made steel case deflector for HK MP5 and MP5K receivers in 9mm and .40 S&W. Installs on the ejection-port flat, rivet or weld, to redirect brass and...
    HKP-22383
    $24.95
    Qty in Cart: 0
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    $24.95
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