Been saving all my .223 cases. Gonna get a reloading kit soon. Got around 300 empty cases. I notice at the front of EVERY case where the bullet goes in there is a small flattened side. Its only about 35 degrees of the circle and its not completely flat, but it does have a little bit of a flattened side. The gun shoots .5 moa. It a Remington 700P. Is this normal??? Got a pic below. The flat side is on the bottom of the pic.