Do you have to trim that brass a lot?
If so the case is stretching for some reason.
But another possibility is that a case can be be damaged on the initial firing.
Neck sizing only on subsequent firings, when done properly, will help to prevent any further stretching, but the damage may have already been done the first time out of the gate.
You can determine this by checking the inside of the case after the first time you fire it. That would be useful information to have.
I haven't seen case stretching that looked like your pics so I wouldn't rule out a manufacturing defect at this point.
