Well built, flawless function thus far - Aero Precision M4E1 Threaded 8in .300 Blackout Complete Upper Receiver with Flash Hider

I coupled this with an Aero pistol lower (came with their carbine buffer) direct from Aero Precision. I’ve run ... 11 different types of ammo through it including 3 subsonic loads, and have not experienced any malfunctions or failures as of yet. Subs cycle completely every time- she’s for home defense so I wasted a lot of $ proving this to myself. I’m only at a 450 round count so far, and will update if anything changes or if I win the lotto and go to town. The space provided for the forward grip is awesome. It’s very thin and I can get a complete grip on it. It doesn’t get too hot, but I certainly haven’t tried to burn the thing down. It feels exceptionally light. I just love the thing.

For .300 blackout newbies like myself:
I’ll say that switching from a 5.56 pistol, it’s amazing how little flash there is from the .300AAC. More recoil, but it’s almost like a slow push as opposed to a punch like with other 30 cal rounds. Hard to explain, but it’s just muted or smoother. My wife actually prefers this over the 5.56 pistol because there’s no fireball in her face.

The subsonic loads almost feel and sound like they’re just falling out of the barrel- until you look at your 50 yard target and realize you’re shooting a standing group in the same location as the SuperSonics with half the noise. Fun stuff, and great for home defense. Now during this corona virus isolation, my wife and I have been practicing room clearing together as a family. And writing reviews.