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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 bullet that may have been reloaded. Also notice the difference on the pin on this and the other similar one compared to the rest of the UMC ones.
picture of Union Metallic Cartridge Company pinfire cartridge
Picture of Union Metallic Cartridge Company headstamp