Wondering if this wear look normal to you all.  It is on an older LE prefixed 6920 with rollmarks era carbine running the factory colt BCG.  Maybe just a few small trips to the range.  My other ARs all show some light wear in this area, but this look pretty rough in comparison.

Are the bcg rails smooth?

Yeah, smooth.  Looking at this more the wear isn't/can't come from the BCG rails.  They are very narrow and I can see where the bcg rails make contact with the receiver and it not even in these patches of "wear".  In fact there seems to be a gap of air between the BCG and receiver in this "wear" area.

Beginning to think this is some kind manufacturing defect that was always there and I just never noticed it before.

The picture quality is pretty poor, but I don't really see anything to be concerned about in the respect to which you are asking.  I would be more concerned about what appears to be excessive erosion at the rear of the receiver where the charging handle seats.  It almost looks like an improperly made charging handle is smashing into the receiver.

If you are using a stock Colt charging handle, THAT seemingly excessive pounding, AND the wear you are asking about, together, could be an indication of a material quality problem.

But again, it is hard to tell by that picture.

I know this will come as a shock...But when the gun is acually being used, that large metal mass will move back and forth inside that aluminium frame covered in anodization....and create wear spots...

Keep the gun well lubed and it will perform well for you.





The buffer pic is extreme wear, because it had a shit load of rds, but the rest are your normal wear and tear.

And the buffer still works just fine.