Local Boy - That's a good comparison and stop-gap idea. I imagine that it has been done.

On the rare occasions that I have seen early Krags with cleaning-rods, at gun-shows, they have sometimes had 'brass-tipped' rods. The rods, even all steel ones, have looked 'suspect'.
For a hobbyist seeking to fill a hole, it would be a lot easier to make a substitute rod with a brass-tip, than a 'flared' steel one.

IIRC - The real Krag brass-tipped rod use was short-lived and the rods are very rare.

Out of curiosity, I measured the steel rod on my (7mm) No.5 Remington Rolling-Block rifle. The Rod was about 1 inch too short, too small in diameter, and the screw thread was cut similar to a wood-screw.

(I like your 'comparison list', but, I think the Krag thread is probably 26 TPI).

If Jon's Machinist friend can make him one to Mallory's specifications, that would be pretty cool. If he could make multiple ones, at reasonable cost, he could make several people quite happy!

A 'stop-gap' rod that is too short would look odd. The 'flared part' of the rod has a visual relationship to the Krag's muzzle area.

(I suppose an 'extension' could be added to a substitute rod that is too short. FWIW - I would prefer a 'correct' replica).

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