Shot shell external corrosion - General Ammunition Discussion

What are these calcium looking buildups? I cleaned the one on the left. And it appears there is no cartridge wall breach (no hole). They are all live “REM-UMC No.12 Best” headstamped.

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Rottweil shotshell 2012 by Kuhada - Issuu

Henry Lever Action Henry Repeating Arms

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Ver·di·gris, really? - General Ammunition Discussion - International Ammunition Association Web Forum

Shot shell external corrosion - General Ammunition Discussion - International Ammunition Association Web Forum

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Hunting & Target Shooting 2024/25 RWS GmbH by RWS GmbH - Marken und Kataloge - Issuu

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The brass cartridge with a jacketed bullet have been the dominating firearm ammunition for almost 150 years. What will be the next evolution in firearms? - Quora

Shot shell external corrosion - General Ammunition Discussion - International Ammunition Association Web Forum

Shot shell external corrosion - General Ammunition Discussion - International Ammunition Association Web Forum

Shotshells