摘要
目的研究QSZ92式9mm手枪射击弹壳击针头痕迹的稳定性。方法选取5支全新的92式手枪,实验提取每支枪发射产生的第1枚至第3070枚弹壳。将第1至20枚弹壳全部录入Evofinder~枪弹自动识别系统,从第21枚开始,按照击发顺序每10枚随机选取1枚录入,即每支枪录入325枚,5支枪共录入1625枚。用5支枪第1枚弹壳击针头痕迹在各自第2~20枚弹壳数据库、第2~3070枚弹壳数据库及5支枪混合1624枚弹壳数据库中检索,得到相似度与排名,用统计学Minitab17~软件分析数据,量化考察击针头痕迹的稳定性。结果5支枪表现相同,同一支枪第1枚弹壳与第2~3070枚弹壳相似度高于其与其他枪支弹壳相似度,第1枚弹壳与第3070枚弹壳图像比对相符大于差异。结论 QSZ92式9mm手枪第1枚弹壳与第3070枚弹壳击针头痕迹具备足够特征同一认定,在使用寿命内,击针头痕迹因击发次数增加产生的差异小于不同枪支间的个体差异。
Objective To investigate the persistence of firing pin impressions from QSZ92 9mm pistol by ballistic identification system Evofinder？. Methods Each of 5 selected QSZ92 9mm pistols was to fire 3070 cartridge cases. The data of 1st -20th cartridge cases were one by one entered into the Evofinder system. From the 21st, any random one was selected out of every 10 consecutive firing cartridge cases, having its data entered into the Evofinder？ system, too. Thus, a database of 325 cartridge cases was established for each pistol, together with the one of 1625 cartridge cases for the total of 5 pistols. The first cartridge case fired by each pistol was then correlated against its own database of the 2nd-20th cartridge cases and that one of the 2nd-3070th cartridge cases, as well as the one of 1624 cartridge cases from all the 5 pistols, respectively. Ranking was accordingly made for the correlated cartridge cases to have been calculated their similarity to the involved 1st one, with the resultant data to evaluate the stability of firing pin impressions by statistical analysis of Minitabl7？ software. Results For each one of the 5 pistols, the first cartridge case showed better similarity to its other 2nd-3070th ones than any one from the other 4pistols although such similarity was going down slowly. Yet, the similarity was greater than dissimilarity in comparison of the first cartridge case＊s image with that of the 3070th one from same pistol. Conclusions Firing pin impressions, even between the first cartridge case and the final 3070th one of same QSZ92 9mm pistol, still retained enough identical traits to conclude that they were resulted from the same pistol because of their lower difference out of a lifetime-effective pistol’s firing times than that from the substantial discrepancy among different pistols.
出处
《刑事技术》
2017年第3期182-186,共5页
Forensic Science and Technology
基金
上海市刑事科学技术研究院物证重点实验室开放课题(No.2016XCWZK02)
