HK MR556 A4 | 2 Uppers Tested, Warranty Experience & Accuracy Results
This video provides an in-depth review and comparison of two HK MR556 A4 upper receivers. The content details initial inspection issues with the first upper, its warranty experience with HK, and a side-by-side comparison of both units. It features detailed borescope footage of critical components, comprehensive accuracy testing with multiple ammunition types (Federal Gold Medal 77gr SMK, Hornady 73gr ELD Match, IMI Razor Core 77gr, Winchester M193) at 100 yards, including velocity data, group measurements, and A-ZED scoring. Key findings highlight manufacturing variation and performance differences between the two uppers.










