Spiders, Wasps, and other insects are known to have nested in rifle and gun bores causing serious bore damage.

I remember reading one African Hunter's account of inserting cartridges, bullet-end first, in the muzzles of the hunting rifles, stacked around the Safari Camp. This was to prevent insects from building mud nests in the bores. Such an obstruction could be catastrophic.

IMHO - Your Krag's stock is likely repairable. Possibly, the barrel could be salvaged by counter-boring.