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
-
HK MP5 Magazine Release - Extended Streamline - EMR
HKP HK Parts
$44.95HKP HK Parts Extended Magazine Release - EMR - Streamline for HK MP5 Elevate your paddle style mag release with the streamlined extended mag release. Crafted from a solid billet of...HKP-22175-M$44.95 -
HK MP5 Receiver Flat with Weldment Set - 9mm
HKP HK Parts
$219.95HKP HK MP5 9mm Receiver Flat with Weldment Set New MP5 receiver flat and weldment set combined for the best complete build option on the market. Made by the original German tool and die maker of the...HKP-20920$219.95 -
HK416, MR556 Ejection Port Cover
H&K Heckler & Koch
$58.95H&K HK MR556/416 Ejection Port Cover HK manufactured newer polymer style cover assembly found on the latest HK 416 & MR556. This item can also be used on other AR15-style projects to enhance the...HKP-15229$58.95 -
Out Of Stock
HK MP5, MP5K Paddle Magazine Release - Anti-Rattle Roller Tipped - 9mm
HKP HK Parts
$49.47HKP HK Parts 9mm Anti-Rattle Roller Tipped Paddle Magazine Release for HK MP5 and MP5K Latest generation paddle mag release for all 9mm MP5, MP5K style builds. Made to the latest German specs,...HKP-17570$49.47 -
HK UMP Lower Locking Pin
HKP HK Parts
$12.95HK UMP Lower Locking Pin, Push Pin For use with all HK UMP lowers & USC to UMP conversions. Made in the USA. This is the pin that holds the lower to the receiver. Compatible With:HKP-18580$12.95 -
HK SL8, G36 Magazine Release - Extended
H&K Heckler & Koch
$19.95Heckler and Koch Oversized Extended Magazine Release for HK SL8 and HK G36 New HK German HK SL8, HK G36, HK243 extended mag release. A must have upgrade for yHKP-17720$19.95 -
HK MP5 Trunnion - 9mm
RCM
$64.95RCM MP5 9mm Trunnion US made to exact factory HK specifications and machined completely from ordnance grade steel and heat treated to factory specs. Compatible With: MP5, 94<HKP-01193$64.95 -
HK416, MR556, HK417, MR762 Buffer Retaining Pin
H&K Heckler & Koch
$15.95Heckler and Koch HK MR556, HK MR762, 416/417 Buffer Retaining Pin New HK German proprietary HK designed buffer pin unique to the HK 416 and MR 556 series. Compatible With: HK416, MR556 HK MR7HKP-02544$15.95 -
HK MP5 Receiver Flat with Weldment Set
PTR
$294.95MP5 9mm Receiver Flat With Complete Weldment & Rivet Set - PTR/LSC Several years ago PTR bought out LSC and now owns the tooling and dyes for the LSC 9mm flats. These elusive flats have been hard to...HKP-19509$294.95 -
HK416, MR556, HK417, MR762 Takedown Pin Detent Spring
H&K Heckler & Koch
$9.95H&K HK MR556/MR762/416/417 Takedown Pin Detent Spring New HK German manufacture. Detent spring for the rear takedown pin. Compatible With: HK MR556 HK 416HKP-02541$9.95 -
HK91, G3 Magazine Release Set
H&K Heckler & Koch
$34.95Heckler and Koch Magazine Release Set (Left to Right) for HK91, G3 This HK German manufactured magazine release set for HK .308 pattern rifles consists of 4 pieces. Includes: Magazine CatchHKP-00929$34.95
HK MP5, MP5K Cartridge Case Deflector, Shell Deflector - Billet
HKP HK Parts
$19.95Cartridge Case Deflector, Shell Deflector - MP5, MP5K - Billet New US made case deflector for receiver flat or receiver for all MP5, HK94, MP5K, & SP89 builds. The case deflector is riveted or welded...HKP-17574$19.95