![Why do they call it a "battery" cup primer? - General Ammunition Discussion - International Ammunition Association Web Forum Why do they call it a "battery" cup primer? - General Ammunition Discussion - International Ammunition Association Web Forum](https://global.discourse-cdn.com/business6/uploads/cartridgecollectors/optimized/3X/3/7/3726f12a23d1f194bae788502083c0cc18b28e04_2_690x215.jpeg)
Why do they call it a "battery" cup primer? - General Ammunition Discussion - International Ammunition Association Web Forum
![Review: Determining the Effect of Cartridge Case Coatings on GSR Using Post-Fire Priming Cup Residue - Florida Forensic Science Review: Determining the Effect of Cartridge Case Coatings on GSR Using Post-Fire Priming Cup Residue - Florida Forensic Science](https://www.floridaforensicscience.com/wp-content/uploads/2017/07/Determining-the-Effect-of-Cartridge-Case-Coatings-on-GSR-Using-Post-Fire-Priming-Cup-Residue.jpg)
Review: Determining the Effect of Cartridge Case Coatings on GSR Using Post-Fire Priming Cup Residue - Florida Forensic Science
![Battery cup primers, history - General Ammunition Discussion - International Ammunition Association Web Forum Battery cup primers, history - General Ammunition Discussion - International Ammunition Association Web Forum](https://global.discourse-cdn.com/business6/uploads/cartridgecollectors/original/3X/c/f/cffeb07f5cf7bcba227af619b8f62b1a6ca3296a.jpeg)
Battery cup primers, history - 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/47ez10m63tq91.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
![Side and top views of a percussion cap, comprised of the primer cup,... | Download Scientific Diagram Side and top views of a percussion cap, comprised of the primer cup,... | Download Scientific Diagram](https://www.researchgate.net/publication/336659708/figure/fig2/AS:815522039996427@1571447014540/Side-and-top-views-of-a-percussion-cap-comprised-of-the-primer-cup-anvil-and-primer-mix_Q320.jpg)