Aero 10.5" upper - Aero Precision M4E1 Enhanced 10.5in 5.56 Barrel Quantum Handguard Complete Upper Receiver with Flash Hider

I mated this with my pistol lower and went straight to the range. I was able to adjust my Trijicon MRO (2 MOA) to zero at 50 yards with 6 rounds and confirmed my 50 yard zero with 5 more rounds. I printed a 1" group at 50 which is fine with me for my setup. After that, I ran 90 rounds of 55gr M193 and a 20 round mag of 77gr IMI Razor Core. No malfunctions and all brass ejected between 3 and 4 O'clock. My bolt carrier group was pretty dirty after only 121 rounds and, if that is my only complaint, I'm pretty happy with this 10.5" upper.