need some insight

[CaffeinFeign]

bought this Ruger LC9 (new) for my wife as her third gun for carry. she came home from the range yesterday and I tore the gun apart to clean it for her. (yes I clean her weapons....just bought a sonic cleaner...and it is a wonder) Anyway, as I went to clean the frame...I noticed this... there is a groove in one side of the frame and another forming... there are less than 300 rounds in this gun. 250 rounds of 115gr FMJ and 50 rounds of 124gr FMJ. All by normal companys. I have never seen this happen before and am stumped..what would cause the shell to do this....? any thoughts?
sorry for the pics...they are the best I can do with a cell phone...

[giantsfan]

I have similar grooves in mine but not as extensive as yours. I've got just a little under your round count.

Doesn't look abnormal to me though. It looks like where the breech rests on the lower frame. When you pull the slide back the chamber/breech/barrel assembly comes back slightly with the slide then reseats against the frame for firing causing the wear marks.

Is that what you're seeing?