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this is where we are going to do the test firing um to get our distance tests where we're we're going to fire our
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suspect firearm um using both suspect ammunition and laboratory ammunition for comparison and we're going to fire into
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our test fabric at known distances what's the difference between suspect ammunition and lab ammunition there was
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ammunition that was emitted with the suspect revolver um so this is ammunition that was actually uh removed
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from the cylinder of the revolver at the time we need to test fire laboratory ammunition along with the suspect
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ammunition because the ammunition that's used has a great effect on the residues
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that are left on the surface so it's a reproducibility we don't have a lot of ammunition from the scene we have a lot
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of lab ammunition so we want to make sure although we've gotten the same type of ammunition we want to look at the
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reproducibility of our ammunition uh to the suspects this particular revolver is
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not the one that was collected for evidence when we did the actual testing it was indeed the revolver that was uh
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submitted by the law enforcement agency that was collected at the time this is actually a firearm from our laboratory
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collection we keep a Firearms reference collection and where they're from is they're actually from actual cases
00:01:32
through throughout many years once the the the criminal case has been finished um many of those Firearms will actually
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end up being destroyed you really want to try to limit your variabilities that's why you want to make sure that
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there is reproducibility between uh the same ammo uh that we're using and that the suspect has that's why we use the
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same gun the what we can't reproduce is skin so there's clear variability between twill and Skin So
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you want to reduce every other variability so you'll be firing into the twi how far away at the time that we did
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the test we used the actual evidence revolver and we used both evidence ammunition which we had a limited supply
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of and we fired tests at 1 in 3 in 6 in 12 in and 18 in you shoot you look at the pattern and
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you want to get the two brackets so it's definitely greater than and the larger one out definitely less than and uh
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that's what we looked for first so the 1 in and 18in it was definitely within those
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we don't know exactly um how skin reacts compared to the white cotton twill so therefore we're we're developing a
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conservative bracket and we're looking for those end brackets that are obviously different than what the
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pattern was in the skin how accurate is this test I think it's has a range it's not going to be one to one it helps you
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it's a tool just like anything else it's a tool it's not an answer uh per se that's why we have to give a bracket uh
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it is accepted uh scientific working group accepted this methodology for giving a rough um Range