S&W M&P 9c: Slide Rail Cut/Chip?

[TunnelRat]

Hi all,
So I went today for another range trip with my M&P 9c. Was a good day, shot well, and came home to clean it. I was cleaning the slide when I notice a small cut on the slide rail right above the firing pin block. At first I thought it was a chip out of the rail, but on closer inspection it looks like a radiused cut that was machined into the rail. It's not very deep into the rail, but it has me puzzled.

Anyone know what this is? Should I be worried? The gun has been flawless but a flaw in the slide rail is something I don't want to mess with. I took a picture of the same spot on my fullsize M&P 9. You can make out a small line in the same location but no radius like on the C. I have shot the fullsize less, so maybe the cut hasn't formed yet? Both guns have casings dating to last month within a week of each other so if it is a metallurgy problem it might be a batch thing. All I've ever shot in them is standard pressure ammo.

Thanks,
-TR

 

[Wreck-n-Crew]

Looks factory to me ...at least from the angle of the photo.

 

[TunnelRat]

Agreed, my question is for what and why is it different than the fullsize?

Edit: The other fact is there is no finish on that area. So if it was machined it was done after the finishing.

 

[Wreck-n-Crew]

Take a look at your trigger mechanism on the other half ....should be able to line them up similar to this

Maybe it was done as an afterthought or correction to design....but im guessing when you line yours up you will see something.

IF not and you have taken it that far in your inspection, may have been some type of accident when boring the hole and had no effect to function and passed QC.

I have see that before in guns and car parts, where it didn't affect the function and passed, shipped and installed.

 

[TunnelRat]

If not and you have taken it that far in your inspection, may have been some type of accident when boring the hole and had no effect to function and passed QC.

Hmm, I think this is right on the money. They drilled the hole for the firing pin block and when backing out the bit accidentally touched the slide rail. Good detective work!

 

[Wreck-n-Crew]

Thanks