'Rock' - I am going on the slightest of clues, but, I think your Krag is a 'parts gun' put together by Francis Bannerman and Sons.

Your Stock looks to be adapted from a 1903 Springfield stock. This was a practice of Bannerman's to utilize their stash of surplus parts.

The sure proof would be stock cross-bolts and a 'wood plug' closing off the bottom magazine opening.

Attached - OP's photos showing 1903 cut-off recess and cross-bolt. These features are not found on Krag stocks.

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