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
-
HK417, MR762 Castle Receiver Extension Nut for Buffer Tube
H&K Heckler & Koch
$44.95H&K HK MR762/417 Castle Receiver Extension Nut For Buffer Tube - Black New HK German manufacture and the factory correct offering with the proper installation screws and staking guides. Compatible With: HK MR762 HK 417HKP-16768$44.95 -
Out Of Stock
HK G36 Backplate with Recoil Buffer - US
USA
$44.95HK G36 Backplate With Recoil Buffer New G36 Backplate with new G36/SL8 recoil buffer. This is a great spare or replacement to have on hand. These are also required for those that are doing the SL8-G36 conversions provided by Tommy Bostic & Chopstix...HKP-18538$44.95 -
HK G36, SL8 Cocking Handle Axle Pin - USA
USA
$10.95HK G36, SL8 Cocking Handle Axle Pin - US Made This is the rivet pin that is used to attach the swiveling cocking handle to the body of the carrier. These can be replaced as they break and wear. Compatible With: HK G36 models HK SL8 modelsHKP-18367$10.95 -
HK G36, SL8 Complete Recoil Rod Assembly
H&K Heckler & Koch
$69.95Recoil Rod Assembly for HK G36 & SL8 New HK factory German G36/SL8 (fits all variants of SL8/G36) recoil rod assembly complete. Great for replacement or for a spare as these have been hard to find.HKP-01057$69.95 -
Out Of Stock
HK MP5, MP5K Case Deflector
H&K Heckler & Koch
$0.00HK German case deflector for receiver flat or receiver for all MP5, HK94, MP5K & SP89 builds. The case deflector is riveted or welded in place on the ejection port of the 9mm receiver/flat to aid in the extraction of the 9mm round. HK MP5, 94 HK...HKP-00871$0.00 -
Out Of Stock
HK G28 Buffer Tube
H&K Heckler & Koch
$199.95HK G28 Buffer Tube / Receiver Extension New HK German buffer tube with the proper slot cut for use with the G28 stock. This is the factory correct part needed to get the full range and use of the G28 adjustable stock. Made in Germany by HK.HKP-16741$199.95 -
Out Of Stock
HK416 Upper Receiver Kit - 10.4" - 5.56
HKP HK Parts
$2,485.95HKP 416 10.4" 5.56 Complete Upper Kit Complete Each kit includes the complete upper assembly, bolt group, tungsten buffer, & high-reliability SS recoil spring. This upper kit is a complete gas piston HK 416 style upper assembly that will drop on your...HKP-17662$2,485.95 -
HK 416, MR556 Charging Handle Roll Pin
H&K Heckler & Koch
$7.95HK Clamping Sleeve or Roll Pin for Pawl On Charging Handle This is the longer one that is used on the outside of the charging handle. There are one of these pins used per charging handle.HKP-17063$7.95 -
HK MP5 Receiver Flat - Smooth Top
HKP HK Parts
$125.95HKP HK MP5 Receiver Flat - Smooth Top The MP5 receiver flat has been meticulously crafted by the original German tool and die maker of the LSC receiver flat, utilizing factory original German prints and specifications. This receiver boasts a flat top,...HKP-21552$125.95 -
HK MR556, MR223 Upper Receiver w/ F/A & Ejection Door
H&K Heckler & Koch
$694.95New HK German Partially Pre-Assembled MR556/MR223 Upper Receiver Each unit comes just as shown with the F/A (forward assist) assembly and ejection port door assembly installed from the HK factory. Compatible With: HK MR556 HK MR223 HK...HKP-16950$694.95 -
HK416, HK417, MR556, MR762 Takedown Pin - Rear - A4 Style
H&K Heckler & Koch
$43.95H&K MR556, HK416, HK417, MR762 Rear Takedown Pin Factory A4 rear takedown pin. Will work for A1 and A4 applications. Compatible With: HK MR556 A1 and A4 HK416 HK MR762 A1 and A4 HK417 AR-14, M4, M16HKP-22029$43.95 -
HK MP5 Lower Receiver - Section
H&K Heckler & Koch
$54.95HK MP5 Rear Receiver Section HK German demilled receiver section with rear sight base as installed at the factory. The rear push pin section is still attached to the demilled receiver section.HKP-02147$54.95