Confederate

Selma

DIAMETER: About 4.90 inches
GUN: Unknown
LENGTH: About 7  inches
WEIGHT: About 35 pounds
CONSTRUCTION: Bolt                SABOT: Copper, Cloverleaf
FUZING: None

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A typical Selma bolt with cloverleaf sabot.  No American gun of this caliber is known.  Possibly for a re-bored 12 pounder.