A toothbrush and some Hoppe's would probably clean up the sight, in question, nicely. (I now think it's correct, but, greasy & dusty, which made it suspect).

Attached are photos of a Krag model 1898 rifle and model 1899 carbine front-sights to show rather typical appearance of sight base attachment.

IMHO - With short Krag barrels, (22" & 26"), this is the first place to look for 'mischief' and fakery.

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