Reliable with the right components
Fired 3 full mags (90rds) with no issues. Feeds, fires, ejects fine (both 115 and 124gr hardball, mixed). Paired this with a PSA m4 type lower with Pmags/Endo conversions. Running a bolt with external m4 extractor, cut for both Colt and Glock mags backed by a Foxtrot Mike extended, heavy, 9mm buffer and standard carbine spring. Last round bolt holdopen works fine. Recoil is no different than a 5.56 AR, but blast/noise is lower with the 9mm. I didn’t bench rest it, but there was no issues hitting with open sights. Groups better than any of my 9mm handguns.
Overall, I’m really glad I purchased this upper. It was easy to assemble (no gas system to mess with). Upper has a pistol cartridge size ejection port and no forward assist (bolt has no forward assist cuts anyway), M4 cut phosphate bbl with A2 comp. Mine didn’t come with the handguard pictured in the description, but I like it anyway. Feels light and slim but strong enough. I recommend this upper.
Reviewed by: Darren from Greenville, SC on 9/20/2020