9mm Case Crushing

While shooting my 9mm Range Officer yesterday I would sometimes get a crushed case on the last round out of the magazine.  The case would eject but the mouth seemed to come in contact with the front of the slide on the way out causing it to crush.  It's so bad the case is no longer useable.  What is the cause/fix?

lower your recoil spring a couple of pounds

DavidR wrote:lower your recoil spring a couple of pounds

I was half expecting that response but considering how snappy the rounds seem I wasn't sure.  Any idea what tension is on the stock Springfield 9mm RO?

Did a little checking and apparently the stock recoil spring is 9 lbs.  I ordered an assortment of springs from Wolf.

Whatever it is it was designed for full power factory ammo, so if its not functioning with lower power factor ammo it needs to be less weight.