'Wolfsburg' - Welcome to the KCA Forum. You have a very nice looking model 1896 Krag rifle.

Looking at serial number production estimates, calculated by the late-William Mook, places the manufacture of Krag, #99403, at around April, 1898.
Joe Poyer's book (appendix tables) places manufacture at around June, 1898.

It is rather certain your Krag was first manufactured sometime, between March and June, 1898.

Most Krags were returned to Springfield Armory or various arsenals & depots, during their use in service, for inspection and repair.

When this process occurred, Arms were inspected, taken apart, serviceable parts refinished and put in parts bins, and eventually the parts were randomly drawn and assembled into a 'rebuild' or reconditioned arm.

"Rebuilding" explains how a rifle stock, with an 1897 'cartouche', ends up with a barreled-action assembled in 1898.

(I corrected my initial post. The photo of left-side of Wolfsburg's bolt-sleeve confused me):

The 'ribbed' bolt-sleeve, with its extractor retained by a screw, is an updated model 1892 type.
Some of the early 'ribbed' bolt-sleeves were altered to use a regular 1896 or 1898 Safety-Lever. These are sometimes seen on model 1896 and 1898 Krags.

IMHO - These 'recycled' early bolt-sleeves are an interesting part variation. I suspect this was not the bolt-sleeve on Wolfburg's model 1896 Krag when it was first built.

p.s. - The nickel-plated cartridge size oil containers show up and sell for about $15 to $20. (Grandpa's Gun-Parts in KCA Classifieds has Oiler for $18).

Attached - Photos of a Springfield Armory modified early bolt-sleeve, (for re-use), and one in original form.

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