I just gave that one a look over and it looks like what Phil surmises. . . . . . carried a lot and shot a little.
The reason I say that is I've seen plenty of these when they showed up for any work and this has that look. If you look at the edges, they are worn a little but, overall, no tell tale marks from abuse. The grip screws look untouched and sharp, not all beat up and stripped. It's serial number is in the mid 3700s, a good time for us. The trigger and mag release are not beat up. Overall, my hunch it is a great carry suspect. Looks like the extractor isn't out of line or "used up" so much. Clean in it's lines except "Throwing it around like a tool". . . . . and I mean like a tool, something to use when performing your job or tasks, not a tool like the person was a jerk with no respect for the unit. He actually used it as designed.
Anyway. . . . . that's my thoughts on it.
Enjoy the weekend gents. . . . .
Eric R.