'Ora' - You asked which Krag rear-sight would have originally been on your model 1899 carbine?

It is likely your carbine, #281611, was made late enough that it 'escaped' being issued with the 'three notch' model 1898 sight (carbine version).

Initially, it may have been issued with a model 1896 carbine sight. If so, later this was likely replaced with a model 1901 or model 1902 carbine sight. Rear sight updates are an amusing chapter in the U.S. Krag Story.

Be forewarned. 'Loose' Krag carbine sights are hard to find and routinely bring prices ranging from $200 to $600.

For your purposes, (on a 'shooter'), the much cheaper rifle versions of the model 1896, 1901, or 1902 sight will work. The 1901 and 1902 sights are adjustable for windage. Replica (30 tpi) sight screws are available from S&S Firearms, Glendale, N.Y., (catalog is viewable online).

BTW - Redfield made versions of the #102 Sight for a wide variety of Military and Commercial rifles. The correct 'Elevation & Windage Slide' for your #102-K base will have a small "k" stamped on the bottom of the crosspiece. (Other 102 'Slide' variations, likely will not 'center' properly on a Krag).

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