Saginaw S'G' pics

[Harlan (Deceased)]

Rustship is correct Bob (if I understand what you're asking about)
I think it's an illusion from a poorly lighted photo. You can see the curvature at the front here.

I'm not sure if this helps, but I zoomed with photoshop and cropped the areas, then placed them side by side in PowerPoint.

[USGI]

Yes, that does help! The arrow that I added wasn't meant to call attention to the punch mark - I was trying to point toward the whole area which appears to be sloping upwards in front of the sight, instead of downwards toward the bolt area, as it should. It's the area that's in the shadow of the Type III sight that appears to be causing that illusion. Thanks ! - Bob