No Dremel!!!!!!
Does one of these 'tight' cases have a 'bright' spot on it.

One other cause of chamber problems can be if the bridge is drilled and tapped with the hole being too deep and either protruding into the chamber or pushing thin metal into the chamber, then it reverses when a round is fired, creating a divot in the chamber wall. If there is a bright spot showing this, have a close look at the top surface of the chamber. You may have to take the barreled action off the stock to check this.

As Marrakai says, protruding primers or case head separation ONLY happens with a headspace problem - either the brass or chamber is at fault.