I totally agree with Parashooter!

FWIW:
In my experience, most Krags with model 1892 and model 1896 rear-sights will have a 'thick-headed' screw anchoring the front hole of the sight base. I believe this dates back to the 1892 sight. It is OK.

There is a model 1896 front screw with a thinner head. (This may have been intended for carbine sight use).

The model 1901 sight had a totally different front screw (with no flange), this allowed it to anchor the lower-base, while allowing the upper-base to pivot.

The model 1898 and 1902 rear-sights had identical screws, front and rear.

The 'short' Krag sight-screws can often be interchanged and will work OK. This probably caused them to be mixed and interchanged over the years.
(This probably happened at Springfield, at arsenals, with 'field armorers', as well as, by hobbyists). 

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