While looking down the carburetor in fully closed position, I can VERY CLEARLY see the slot on the barrel where the barrel set screw goes into. I've had problems before where the throttle barrel won't close completely, but I've never seen the barrel slot being visible when carb is closed. Is this possible on some engines?

This is a brand new MDS V2 carb that just arrived today from HorizonHobby. I don't believe they would send out detective parts on a repair order. Any help would be greatly appreciated.