I did not know where to post this, so I posted it here. I took my AR-15 pistol (300 BO) out today. I think this might even be the first time I have ever fired it. It chambered and fired a round but would not eject. So I came home and thought it was the gas system. I hooked a tube up to it and blew through the tube and there were no restrictions. So I checked the bolt to see if the key was loose, no it was tight. So I took the gas system apart to make sure it was centered on barrel. It was. It ejects manually great. Anyone have any suggestions? Anything I might have overlooked? All ideas appreciated.