Department of Applied Science, Security and Resilience, Cranfield University, Shrivenham, Swindon SN6 8LA, UK.
Forensic Sci Int. 2010 Jul 15;200(1-3):21-7. doi: 10.1016/j.forsciint.2010.03.018. Epub 2010 May 21.
The external temperature of the cartridge cases of 9 mm parabellum ammunition during the firing sequence was measured by a series of methods. Using a thermal imaging camera was the most successful method and showed that aluminium alloy cases reached higher temperatures than did brass cases. Peak temperatures for brass cases were 336 K at the case mouth after 1.2 ms and 331 K at the case base after 2 ms. Corresponding temperatures for aluminium alloy cases were 363 K at the mouth after 0.8 ms and 372 K at the base after 1.2 ms. These times at temperature would not be sufficient to destroy any DNA residues left on the case. Measurement of the DNA of fired cartridges showed that DNA deposited on the cartridge case before firing was not affected by the temperatures reached during the firing sequence. Estimates of temperatures to be found in pure aluminium and mild steel cases were made, these indicating that pure aluminium would give higher temperatures than aluminium alloy and steel a lower temperature than for brass.
通过一系列方法测量了 9 毫米帕拉贝鲁姆弹药弹壳在射击序列期间的外部温度。使用热成像摄像机是最成功的方法，结果表明铝合金弹壳的温度比黄铜弹壳高。黄铜弹壳的峰值温度为：在 1.2 毫秒后弹壳口处为 336 K，在 2 毫秒后弹壳底部处为 331 K。铝合金弹壳的相应温度为：在 0.8 毫秒后弹壳口处为 363 K，在 1.2 毫秒后弹壳底部处为 372 K。这些温度持续时间不足以破坏弹壳上留下的任何 DNA 残留物。对射击弹壳的 DNA 测量表明，在射击前沉积在弹壳上的 DNA 不受射击序列中达到的温度的影响。对纯铝和软钢弹壳的温度进行了估计，结果表明纯铝的温度将高于铝合金，而钢的温度则低于黄铜。
