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12mm Pinfire Cartridge

Size: 12mm
Headstamp: U
Manufacturer: UMC - Union Metallic Cartridge Company - Bridgeport, Connecticut, United States
Additional Info: This variation has an odd round ball for the bullet. It may have been reloaded. Notice the difference on the pin on this and the other similar variation compared to the rest of the UMC pinfire cartridges.
picture of Union Metallic Cartridge Company pinfire cartridge
Picture of Union Metallic Cartridge Company headstamp