I receive mine this Wednesday, Open the box and put throw 40 rounds right away, just to see if this rifle can run out of the box with all factory grease. Yes, it's working beautifully with my P-mag Gen 2 without any malfunctions at all. After fire 40 rounds rapidly without stopage, smoke start to come from the handguard, the smell of grease burning is very addicted. Got tired last night, I will crack her open up and see what's inside tonight.
This rifle doesn't seem to like Remington brand 223 but my American Eagle black box fit perfectly.