So I was doing some Googling on Macon Conversion smoothbores and ran across this posting by Southron, who also frequents here!
http://blackpowdertimes.com/index.php?topic=757.0
Basically he had an uncle who was on a work crew in the 1950s working on the original I-285 around Atlanta when a bulldozer crashed through the roof of a Confederate arms bunker left over from the war. It's how he acquired a Macon Conversion smoothbore.
Pretty amazing story!
Steve
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