Firing pin protrusion

I have a Stoeger Stainless Luger and it has always intermittently pierced primers. The only brand of ammo I've fired in it has been the Winchester white box. The only problem I have encountered with it is that after a 100 or so rounds the extractor does not hold onto the shell very well because the residue vents into the extractor recess and gums it up. I clean it out and I'm good for a while.

So my question is what is the protrusion length suppose to be on these pistols? I could chuck the firing pin in a lathe or drill press and dress it up a few thousandths. Please let me know. Thanks.