初探八五式轻型冲锋枪射击弹壳的底部痕迹变化规律

通过对1010枚样本弹壳的观测统计,八五式轻冲在射击10100发枪弹范围内,各类痕迹呈一定的规律性变化。击针头痕较为稳定,痕底特征反映好,初期和后期之间仍有同一认定价值;击针头次生痕、拉壳钩在棱边的刮擦痕、抛壳挺次生痕具有较高的对接比对价值。另外,各类痕迹的位置、形态在一定范围内变化,检验鉴定时不能轻易作出否定,应综合加以分析判断。

Explore on the Change Law of the Marks Left on the Base of the Light Submachine Gun 85 Shooting Cartridge Case

Through the statistical observation of 1010 sample cartridge cases,light submachine gun 85 showed regular change law of different marks in the range of shooting 10100 bullets.The trace of the firing pin's head was relatively stable and the character of the trace was clear.Between initial stage and later stage still exitsted the same identification value.Those marks have higher docking and contrasting value,such as the mark firstly left on the head of the firing pin,the mark caused by the extractor scraping the edge and the ejection port mark.By the way,the negative judgement shouldn't be easily given after test and evaluation and comprehensive analysis and judgement should be required because marks' location and state will change within relative range according to different kinds of marks.