Works perfectly - FM Products FM-9 AR 9mm Rear Charging Upper Receiver, 16 inch

I waited until I got a chance to go out and shoot a Steel Challenge match. Four stages and it ran perfectly. I had an ultra lightweight upper and it just felt like it could fly around. My problem not the ultra light upper. This is heavier but not heavy in my opinion. I also liked getting the full length handguard. I put a Magpul hook to locate my finger so my hand is in the same location each time.