It is a little hard for me to see what the problem is, but but I know what you are referring to. After firing the case head can expand (a tiny bit). When you resize the brass, the head does not get resized. After belling the mouth and seating a bullet, the brass around the bullet is pushed out (again a tiny bit), leaving the middle of the case slightly narrower than the head and the mouth. If you don't have a go/no go guage you can take the barrel out of your pistol (obviously for safety reasons, and a very important step), and drop you bullet down the chamber. It helps if you have some factory loaded ammo to compare it to, but as long as you have not trimmed your brass it should fall in and out easily and headspace properly. I have loaded thousands of rounds. When I first started reloading was concerned about what you are seeing. After showing it to many (if I knew how to underscore many I would), people that reload, I had enough confidence to fire them. Never a failure to feed, never a failure to fire, never any sign of overpressure (of course you have to be obsessively following known good data).