H&K Heckler & Koch
HK MR556 A4 Upper, Complete - Full Auto and Ejection Door
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- SKU:
- HKP-21929
- MPN:
- 50257784, 257784, 51000977
- Condition:
- New
Frequently bought together:
Description
HK Heckler and Koch A4 Complete Upper with Full Auto Ejection Door for HK MR556
The HK MR556 A4 Complete Upper is a superior factory assembly that comes fully equipped with a forward assist and an ejection port door, providing unparalleled reliability and precision. This upper is the ultimate choice for enhancing your rifle or launching a premium build. With compatibility for all A5 style barrels, including those from Nefarious Arms, you can trust that this upper will elevate your build to the next level.
Features:
- OEM HK MR556 A4 complete upper assembly
- Includes forward assist and ejection port door
Compatible With:
- MR556 A4, A5
- Compatible with most AR-15 lowers*
*Minor fitting may be required for non-HK lowers.
Warranty Information
These are taken apart from the complete receivers -SB -LB 6/3/25
Our cost price was $400 our cost price now is $691.50-12/12/25-BM
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Additional Information
Firearm Model: |
MR556 |
Origin: |
Germany |
Color: |
Black |
Caliber: |
5.56 / .223 |
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