Anyone seen this on back of Receiver?

[W5USMC]

To big, way to deep

I think it was the owner who stated:
"For reference, it is a SG subcontracted Inland receiver. The dimple is very shallow and perfectly centered."

[eb in oregon]

I think it was the owner who stated:
"For reference, it is a SG subcontracted Inland receiver. The dimple is very shallow and perfectly centered."

"Shallow" is subjective. Viewing the picture the "dimple" appears about as deep as large in diameter. No punch or ball peen strike can physically do that. Both tools displace material around the strike. A ball mill will, but it cuts and there is no indication of material displacement around that dimple. Merely the opinion of a guy that spent 25 plus years working with and machining metal.