What should be used to make scribe markings on the closure disc of an impulse cartridge?

Using an indelible ink marker to make scribe markings on the closure disc of an impulse cartridge is the most appropriate choice because it ensures that the markings will be permanent and resistant to smudging or fading. This is critical in munitions systems where clear, durable markings are necessary for identification, instruction, or safety purposes during handling and storage.

Markings made with a pencil could easily be erased or smudged, leading to potential miscommunication or errors in munitions handling. Chalk, while visible, is not permanent and can be easily removed or affected by environmental factors. A ballpoint pen might not provide the necessary permanence or visibility, and the ink could potentially damage sensitive components. Therefore, an indelible ink marker is the optimal tool, ensuring that markings remain clear and intact throughout the lifecycle of the impulse cartridge.