This photo is some what out of focus.
That is/was a 9MM case, the head stamp is "P-A 9MM LUGER". The primer is very flat. The typical glock rectangle with firing pin strike has flowed back. This glock must have been a newer one with a supported head.
http://thefiringline.com/forums/atta...1&d=1360368915
Be safe,
OSOK