'Rcat7147':  In studying the photos of your 'new' Krag sporting rifle, I notice the Magazine-Gate appears to be from a model 1898 Krag - (Boxier contour).

Your 'ribbed' Bolt-Sleeve was one of the versions originally made for the model 1892 Krag.
Around January, 1900, many of these sleeves were altered to be more like the model 1896 sleeve.
The main change is that they were machined to use a later style Safety-Lever. Also, there is a filled hole, that once held a retaining pin for the earlier type of Safety.
Your extractor-spring may be fastened to this bolt-sleeve with a screw rather than the later rivet.

Your Krag's 1894 receiver, #20837, was likely assembled into a model 1892 rifle around Sept. to Oct., 1895.
A model 1892 rifle, #20836, was documented by Frank Mallory as being issued in 1899 to the 8th Infantry.
Being one digit away in SRS data (Springfield Research Services) is interesting, but, allows no conclusions.

You have an attractive and useful Krag sporting rifle. I hope you get to enjoy shooting it very soon!

Photos: 1. & 2. ribbed bolt-sleeve - Before and After conversion.
             3. 1896 magazine-gate. 4. 1898 magazine-gate

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