In your lowest picture showing the opened magazines, see that small diagonal line in the bottom front area of the mag? That shows something that is not from the Springfield Armory. It has been "dipped" into a bluing vat and it was not fully immersed, so, there is a small diagonal line showing the un-re-blued (original finish) metal.

That's a good example of what Joe Farmer is talking about.

(Copied below-see in lower picture. Top one is just sloppy.)

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