2013 P0-7 Duty.  I only have abouty 1000 rounds through it. Half way through the mag it went "click".  I figured it was just a hard Blazer Brass primer.  Second try was no go.  Drop the mag (after waiting of course) and tried to cycle it.  Locked up.  Gave it some muscle and the slide came back and powder and case went flying.  OH CRAP, bullet stuck in chamber.  I took the barrel out and couple of hard raps on some wood and the bullet popped out.  

Do the firing pins need fitting or are they a DIP?  

Any ideas what caused the bullet damage or why it got stuck?

Is there any evidence of jacket/lead shaved by any sharp edges at the chamber opening or top front edge of the magazine?  Is there any damage to the case mouth?
Further, what leads you to believe the firing pin is involved?

Looks like the bullet was too forward in the case, jammed into the rifling and got damaged when you manually extracted it.
There's not even a faint mark on the primer, so I don't think the slide was forward enough for it to fire.
I also want to know why you think a new firing pin is needed ?
Did you try to fire the 07 again and it didn't fire ?

Are these reloads?

As stated, Blazer Brass ammo.

I took the slide off and pushed on the back of the firing pin.  Nothing protruded out of the bolt face.

UPDATE:  Ok, I'm a moron.  I forgot  the button inside the slide has to be depressed before you push the pin from behind. Firing is fine. So it was either factory ammo error or something else.  I was able to pull the trigger and the hammer did drop both times.

The button is the firing pin block. The lifter will press it when the trigger is pulled so the firing pin can move forward.  Going off a reply above, if the bullet was seated too far forward perhaps it prevented the slide from going fully into battery. Hard to really know at this point...did you shoot anymore after this occurred?

If the slide isn't fully forward the hammer will strike the very bottom of the notch in the slide and doesn't strike the firing pin correctly.

That damage on the bullet looks like it was on the portion that is inside the case.  Can't imagine how that happened.  It's not the kind of mark the lands would have put on the bullet if the bullet had been seated out far enough to strike the lands and keep it from fully chambering.