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Why do they call it a "battery" cup primer? - General Ammunition Discussion - International Ammunition Association Web Forum
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577 Snider Battery Primer Cup Marking - General Ammunition Discussion - International Ammunition Association Web Forum
![Primer cups, the basic concept works now with 0% fail rate, but the unevenness of cups is persistent, idk if it's because of very fine die misalignment, trimming solves problem though, more Primer cups, the basic concept works now with 0% fail rate, but the unevenness of cups is persistent, idk if it's because of very fine die misalignment, trimming solves problem though, more](https://i.redd.it/wdh8vtl63tq91.jpg)
Primer cups, the basic concept works now with 0% fail rate, but the unevenness of cups is persistent, idk if it's because of very fine die misalignment, trimming solves problem though, more
![Primer cups, the basic concept works now with 0% fail rate, but the unevenness of cups is persistent, idk if it's because of very fine die misalignment, trimming solves problem though, more Primer cups, the basic concept works now with 0% fail rate, but the unevenness of cups is persistent, idk if it's because of very fine die misalignment, trimming solves problem though, more](https://i.redd.it/b1n96xl63tq91.jpg)