![]() ![]() The rule must be: label the firing pin shape according to the markings present on the primer’s surface regardless of the make/model gun that fired it. If lab-fired cartridge cases with these markings are classified as “Elliptical (Glock)” but crime-scene recovered cartridge cases are classified as “Circle”, you’ll be creating an environment where no matches will be made between recovered weapons and cartridge case evidence. However, priority has to be given to the crime scene scenario where cartridge cases have been recovered but not the weapon. There will be an urge to label these as “Elliptical (Glock)” when test fires are done in your laboratory with a Glock pistol in hand. With only these features to go by, these cartridge cases should be entered as Firing Pin Shape: Circle. Also gone is the rectangular flowback, which has been replaced by a shear mark extending to the left of the firing pin impression. ![]() The elliptically-shaped firing pin has been replaced by one that is more round in shape, though it does seem to have a flat edge to it at the 9 o’clock position when orientated for IBIS acquisition. The requirement to choose the firing pin shape from the dropdown list must come from the features present on the exhibit itself, which is always at-hand, as opposed to the gun that fired it, which would only be a certainty for test fires taken in-house. As such, a user classifying a firing pin shape should be focusing on “What does this look like?” rather than “What could have fired this?” The former being a basic observation of the shape in front of them while the latter is more analytical in nature, and requires more advanced knowledge. The expert is needed for final confirmation. Taurus PT-22 Firing Pin, Stainless Steel (2529) PT-22 Taurus Stainless Steel Firing Pin. While the end results of IBIS searches can be used by firearm examiners to link previously unrelated crimes, the core purpose of IBIS has always been to be a system operated by technician-level users. To give the most comprehensive answer, we first have to review the philosophy behind how IBIS is used. During creation an IBIS cartridge case exhibit… When should “Glock” be selected as the Firing Pin Shape? New manufacturing developments with Glock firearms have brought forward a question. ![]()
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