Comments
brainwired1 t1_ixay01l wrote
Ballistics matching is a thing, but it's not the hah, magic bullet that Hollywood has made it out to be. If you can recover a bullet and a gun, and you run them through an analysis, it's generally possible to match the lands and grooves of the gun barrel to the mechanical deformities of the bullet. Glocks initially caused a panic when they were introduced, being mostly plastic and having polygonal rifling, because they were "undetectable plastic guns with barrels that left no trace". Bull, of course, but a good political talking point.
fliguana t1_ixb2qxi wrote
Similar bullets leaving the same barrel will have similar markings/scrapes, as they are forced trough the slightly smaller barrel.
Cleaning the barrell should not make a difference, but damaging it with hard substance (sand, aluminum oxide, silicone carbide, diamond dust) would change the barrels fingerprint.
Since barrels are replaceable and are not regulated, replacing the barrell is much easier than messing with it.
PerspectivePure2169 t1_iy1z4cw wrote
I've always wondered about this, as the whole point of mass production and interchangeable parts is to make functionally identical components.
So if two barrels from the same lot of steel are made on the same machines and rifled with the same button, one after the other - how much difference can there really be? There should be nothing but the tooling wear to change it.
Sure one could tell by looking at a bullet if there's a difference in number lands and grooves. Or with some knowledge of various designs' barrels you could say Beretta vs Ruger 9mm etc. But to tell between two Rugers of the same model?
Seems like a stretch to me. But idk.
brainwired1 t1_iy20jyl wrote
You have identified the problem exactly. There's virtually no difference at all between the two barrels as you described. Eventually, maybe, there might be microscopic differences between the two if both of them have been used a lot, but even then it's not the "focus, magnify, magnify, enhance" crap from NCISSICCIENDUF:New Orleans:SPUWIOM.
PerspectivePure2169 t1_iy2174a wrote
Interesting. Had never really thought through it before now. But reasoning through it with an understanding of manufacturing makes sense that the ballistics matching wouldn't be anywhere near a "fingerprint"
More like a copy of a fingerprint 😄
[deleted] t1_ixawbpz wrote
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