Bolt binds in M 16

I bought a new M 16 in .270 Win. Short Mag, a few months ago. The bolt binds when I retract it to the point of stopping solid at times. When this happens, the rear of the locking lugs is flush with the front of the back receiver bridge. If I'm not watching it, this obviously results in a misfeed, which could be very embarrassing, where I hunt. ;D Somehow, I think it must relate to the ejector, because this is the point where it is supposed to pivot up. Any help appreciated, but I am not pleased that this would happen with a new rifle.
Grizz

Im no help, I have not paid much attention to controlled feed actions. But, I did not think the ejector moved.