X marks the spot

[Frank Srebro]

This may have been covered before but I couldn’t find the answer with the search function. Any idea what a X denotes on the forend lug?

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[Randy G Roberts]

To my knowledge that one remains unknown Frank.

[Brian Dudley]

There is no real consensus. The mark can be found in a few different areas from time to time.

[Frank Srebro]

Thank you Randy and Brian for your replies.

[Bill Mullins]

Probably an inspection mark. 🤔