PUBLIC Forums => Research Proposals => Topic started by: MaxYasko on May 13, 2007, 04:17:16 AM
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Do anybody know, is there any reliable method to determine how long ago the shot was made, in a scale of days/hours?
Thanks in advance
Max Yasko
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Are you looking for the time frame based on the impact area or the bullet evidence?
Sincerely,
Kim Haag
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I mean any evidence- impact area, bullet, barrel, etc. It's not about a specific episode, I'm interesting in general. :o
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Significant evidence of a long time interval since the last fire is the accumulation of dust in the bore.
Obviously, the degree of dust accumulation depends on the environment; however, in the case of a very recent shooting where a gun is recovered in a typical environment, a significant accumulation of dust and airborne fibers is a pretty good indicator that you are still lacking your offense gun.
The folks in the former Soviet Union did some studies with the decay of combustion gasses(?) in the barrel of a recently fired gun. The drawback to that approach may be the amount of time needed to conduct comparative lab tests. To get another data to stand up to scientific scrutiny you may need to repeat the test a few times. That may put you past your trial date.
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Mr Shem, thank You for answer to my question. Howewer, by my opinion, such methods are approximate, because observed characteristics strongly depend of surrounding conditions-- temperature, humidity, degree of air motion, content of different reactive substances in surroundings, etc. These various conditions are practically impossible to take precisely into account. I think, it's necessary to consider phenomena that not depend on such conditions. Unfortunately, I can't figure out something appropriate, exept nuclear processes (something like isotopic method). But it's very difficult, if possible at all, to work out something like this in adaptation to above mentioned question.