noun
ejector mark (on a cartridge)
Technical term in firearms forensics or ammunition examination. Refers to the mark left on a cartridge case by the ejector mechanism. Compare with 抽筒子痕 (extractor mark).
See also: 抽筒子痕
現場で見つかった薬莢の蹴子痕を分析した。
We analyzed the ejector mark on the cartridge case found at the scene.
Compound of 蹴子 (ejector) + 痕 (mark, trace). The exact historical derivation is uncertain; the term is a modern technical coinage.