King carp - This is the Krag rear-sight that was used with the 2,200 fps cartridge. This ammo proved too hot for the Krag action and began resulting in cracked Bolt Locking Lugs.

The Carbine version appeared on model 1899 carbines, according to Frank Mallory, made from January to July, 1900.

There was also a Rifle version of this sight.

The sight with three notches was unpopular. (The outside notches were for wind correction).
The 1898 sight was the first U.S. Krag sight that incorporated windage adjustment.

The 2,200 fps ammo was pulled out of service. The model 1898 sights thus became obsolete.

In the early 1900's the 1898  leaf and eye-piece (with the outside notches ground-off) were used to make a variation of the 1902 sight.
(I don't believe the bases were officially reused).

The 1898 sight used the same hand-guard that would be used with the 1902 sight. The same hand-guard was used on rifles and carbines.

The 1898 sights, especially the carbine, are hard to find because the leaf and eyepiece were recycled. They are probably not in great demand.

At the Michigan Show last February, one that I was interested in, was sold for $250. (I'm not that interested)!

Photo - 1898 carbine sight with hand-guard.

p.s. It is not the Krag stock, but, the hand-guard, that needs to 'match-up'  with the rear-sight. The openings in the hand-guard are 'sight specific'.

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