Did I induce damage to my upper receiver?

[ZeroNowhere570]

I have two AR’s I’m going to finish throwing together today. Both are factory BCM Mk2 uppers with BCM BCG’s.

I was hand-cycling my carriers in them (without the bolt, I just wanted to check alignment of the gas tube) and noticed a drag mark on one of the bearing surfaces where the bolt carrier group rides.

There is a small mark just before where the drag mark begins at (at the rearward section of the upper) which appears to be etched. Maybe a small defect from anodizing? I’m not sure. I used a small plastic pick and was able to feel a tiny ‘divot’

I will attach two photos for reference. I don’t believe the carrier actually ‘carved’ a groove (Atleast not that I can feel) I believe it just scratched a line through the grey-ish dry lube film into the black anodizing.

I looked over the BCG very carefully and cannot seem to find anything that would have caused it (burrs, etc.) so maybe this is normal, and well smooth right out once I put some rounds through it. Is this anything that is going to cause trouble?
Thanks guys.

Photos:

https://ibb.co/5rr765b

https://ibb.co/XVd991K

[rpoL98]

it's toast. send it to me for disposal.

just kidding. it'll live.

you might wanna check your carrier (again) for a sharp edge on the corner, or burr.

or maybe you had some (metal) rubbish riding along, shavings, etc.

[AndyLate]

The scratches (for lack of a better word) are not through the anodizing, they are simply where the dry film lubrication is worn/scraped through. If you were cutting/wearing through the anodizing, you would see silver/white aluminum or gold colored anodizing if the wear is shallow. I agree with making sure there are no burrs in your bolt carrier or foreign material on it or the upper, but wear on the dry film lube is not an issue.

Andy