Salty sweat may leave trace fingerprints on metal
Posted 09.05.2008 at 2:40 pm
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A new crime-fighting technique could make avoiding capture more difficult for even the most fiendish gunsels.
The technique, developed by British scientists, allows police to lift fingerprints from bullet casings, even if the casing has been wiped clean. The typical method for recovering fingerprints relies on the sweat from fingertips left on the casing by the criminal. If the casing is wiped clean, then recovering a fingerprint from sweat becomes next to impossible. However, the new technique relies on a substance in sweat that doesn't wipe away so easily: salt.
The salt corrodes certain metals from which bullets are made. In the new technique, the bullet casings are covered with a fine dust. Then a strong electrical charge is run through the metal, causing the dust to stick to the corroded areas of the casing, and revealing a potential fingerprint. Unfortunately, some people simply do not have enough salt in their sweat to create enough corrosion. But the technique does show promise.
So far, British and U.S. authorities have used the new method to re-open three cold cases. John Bond, the physicist who developed the technique -- no relation to James Bond, so far as we know -- said that in one case, enough evidence was produced that the identification of an offender may now be possible.
[Via NewsDaily]
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Why not just cure the criminal with 150 mg of masculine facial skin surface lipid p.o.? That seems even easier. It would certainly be less expensive.
Why not just cure the criminal with 150 mg of masculine facial skin surface lipid p.o.? That seems even easier. It would certainly be less expensive.
from Montreal, Quebec
It's a longshot... last resort I would even say.
Plus, chances are, if you need to perform that technique, the person knew what he was doing and most likely wore glvoes when loading the gun.
- DiGGY
1: NEVER LEAVE YOUR BRASS BEHIND!
2: Load your magazines using 2 layers of disposable gloves.
3: Never violate rule 1.
PS.
Always use frangible ammo (no ballistics) and a .45 Automatic of some type.
Polish breech face, feed ramp, and chamber to eliminate tool marks left from production.
If for some reason you can't hang around to pick up the brass, you can change out extractor, ejector, firing pin, and barrel in less than 5 minutes when you are away from the area.
Dispose of old parts properly, eg. somewhere else from where you are. YOU HAVE A NEW GUN! no marks to identify if weapon should be seized by law enforcement.
Basic agency tradecraft!
from Montreal, Quebec
Are you giving advice on how to not get caught shooting someone... ? lol...
- DiGGY
Yes, it shows how ridiculously stupid law enforcement and the average dumb ass criminal can be!
I'm a former CIA operations Officer.
PPS
Your best bet is a Colt style .45 cal auto pistol. All the replacement parts can be bought over the counter for a few bucks, no questions asked. I prefer the .45; as a hit anywhere on the body or extremities usually stops the confrontation immediately!
OK Boys & Girls, Schools over, now go out and have some fun!
OK J.Lee...
Mythbusters has effectively debunked the hoax about .45APC ammo and the devastating effect of being hit by a 230gr bullet traveling at 950ft/sec...
Altho the affect of a center-mass hit will kill rather well...
Arguing over the internet is like racing in the Special Olympics, You might win, but...
Mythbusters are a bunch of unscientific juvenile clowns. Shooting at ballistic gelatin is crap! I don't shoot 950fps ball ammo, I use hot loads. I also load some of my hollowpoints with potassium cyanide. a hit anywhere is fatal!
I speak from experience. Laos 1962 - Afghanistan 1986. Lots of Soviet Russians found out the hard way.
i think it would be easier just to ditch the gun in the middle of a large body of water (perferably salt water)