Talk:Ballistic fingerprinting

message: I remember hearing G. Gordon Liddy back in 2000 talk about "ballistic fingerprinting".  He said that a more correct term for this would be "Toolmark Identification".
Perhaps the proper name for the article should be something like "Firearm Toolmark Identification" or something along those lines.
It would be a better term than "ballistic fingerprinting" (especially given the fact that guns do not have fingers.)
69.39.172.17 05:35, 16 February 2006 (UTC)
replies: text: Although Google is not a definite source, I find considerable listings for "ballistic fingerprinting".  Toolmark identification might be more accurate, but is not evidenced on Google as being the terminology presently used.  Yaf 06:00, 16 February 2006 (UTC)

text: On what basis do you say the tools Glock uses are not high quality? Jtrainor 22:57, 16 August 2006 (UTC)
replies: text: Have you looked at a Glock pistol?  It's a military arm, made primarily of injection molded plastic, and stamped and welded sheet metal.  The barrels are hammer forged; this requires a million dollar tool, but spits out a rifled, chambered, profiled barrel in a single step ever 30 seconds or so, and if you can afford the machine, it is by far the cheapest barrel making tool in the long run.  Being a military arm, it's designed to be cheap and "good enough".  It is NOT designed to have micrometer tolerances, because if it did, it would cost 10x as much and be horribly unreliable.  Just look at the AK-47's legendary reliability, all due to loose tolerances.  If you want high quality, take a look at the benchrest shooting game.  Reliability is not an issue, precision and repeatability are everything.  Those guys consider a barrel with more than a thousand rounds fired through it shot out...  scot 14:46, 6 October 2006 (UTC)
thread_title: Toolmark Identification

message: As for practical appliactions, ballistic fingerprinting is quite unreliable.  A survey done in California, under ideal conditions, yeilded the following:
:A recent study by the State of California points to further practical difficulties with ballistic fingerprinting. The study tested 790 pistols firing a total of 2,000 rounds. When the cartridges used with a particular gun came from the same manufacturer, computer matching failed 38 percent of the time. When the cartridges came from different manufacturers, the failure rate rose to 62 percent. And this study does not even begin to address problems caused by wear, so the real-world failure rate can be expected to be much higher.
A match in the study meant that the correct gun was in the top 15 best matches; in reality, only the top 10 matches would be considered a hit.  And of course, this is a database with only 792 guns in it; if every gun were "fingerprinted", as many lawmakers want, then of course the database would contain millions (for just newly sold guns) or hundreds of millions (if all are fingerprinted) guns, making a postive ID nearly impossible.  
All the guns were the same make and model--S&W 4006--used by the CHP.  From personal experience with both makes, I can say that S&W uses similar barrel making techniques, and similar machine tools to machine the breech face of the slide.  The S&W firing pin is machined, as it is round, the Glock's firing pin is stamped, as it has a square profile.  Toolmarks should be similar on both guns.  Since matches were possible, that proves that even identical makes and models using the same lots of ammuntion will generate uniquely marked cases; however, the differences between individual cases from the same gun are as wide as the differences between guns.
The only real use of the technique is as a means to assign a probability that a given cartridge case or bullet came from a given gun.  scot 14:46, 6 October 2006 (UTC)
thread_title: Actual effectiveness of Ballistic Fingerprinting database

message: The section entitled "Alteration of fingerprints" has been vandalized to attempt to sell the idea that this process is an established science and has been used in courts, and thus would work on a national level.  The third paragraph is flagrantly POV and should be removed immediately.  The fourth and fifth paragraphs should be in a separate subject entirely, as they have nothing to do with the alteration of fingerprints, but discuss the absence of fingerprints and the inaccuracy of the terminology.  —Preceding unsigned comment added by 70.168.242.17 (talk) 04:22, 12 November 2007 (UTC)
thread_title:  Big Time POV