Those of us who read the Micky Spillane novels might remember that as soon as Micky returned to his office after a shooting, he immediately put a new barrel in his trusty .45 Colt. Takes about a minute or so. Many of the new pistols are even faster to do it.
There is something that I don’t understand. How can two guns of the exact same model and manufacture coming off the assembly line one after the other have different ‘fingerprints’?
How could a bullet, that has hit something not be so deformed that they say that it can be matched to one gun or the other? Does the riflling change that much from one pistol to the next? For the same gun from the same manufacturer? Really?
Are there significant differences between the same model of gun from the same manufacturer? Such that you can identify the specific gun?
Sounds like a lot of BS to me that is just going to drive up the price of guns.
There are two different things being talked about in this thread.
When a barrel is machined, the machine that cuts the grooves for the rifling doesn’t scrape the barrel precisely the same way every time. Every barrel therefore has unique scrape marks left over from manufacturing. Most machining processes leave marks like this. It’s just that exposed surfaces are usually polished smooth so that you don’t see them.
The end result is that even without being fired before, the gun barrel will leave a unique pattern of scrapes along the bullet. Matching it requires that you get a bullet that isn’t too badly deformed. A bullet that lodges in soft flesh will be mostly intact. One that hit a brick wall probably won’t be quite so intact, and you probably wouldn’t be able to match it up. If you have a relatively undamaged bullet, you can usually uniquely identify the exact barrel it came out of due to the pattern of scrapes. Two identical guns from identical assembly lines will be that unique. The rifling in the barrels will be almost identical, but the pattern of scrapes on the inside surface of the barrels will not.
The second thing being talked about is fingerprinting the casing. Not only is the barrel unique, but so is the firing pin. Again, if you just looked at two firing pins with the naked eye they would look pretty much identical, but each firing pin is also microscopically unique, and leaves a unique mark on the shell casing. Changing the barrel doesn’t change the firing pin, and you don’t need an intact bullet to match up shell cases since the case is usually ejected perfectly intact.
Ballistic fingerprinting is one of those things that sounds good on paper, but the huge cost involved and the poor success rate do lead a lot of folks to consider it a bunch of BS that drives up prices for no good reason.
The “ballistic fingerprint” laws are idiotic at best.
Example:
Bob lives in California. He buys a handgun legally at a licensed gun dealership. He fills out all his forms, goes through the background check, the waiting period, etc… It’s perfectly legal.
6 months later during a burglary of his home Bobs handgun is stolen.
1 year later the handgun is floating around the streets of Detroit where some scum bag uses it to shoot an employee at a gas station.
The data base of ballistics shows the bullet that killed the gas station clerk came from a gun owned by Bob in California.
So what?
It doesn’t show who pulled the trigger.
Well, except for the fact that Bob presumably reports his gun as being stolen.
Which then brings up the point…if Bob reports his gun stolen, can he then hold on to it for a few months, drive to the next state over and kill someone, ditch the gun, which may or may not ever be found, and be pretty much in the clear if it is found?
Another point to note is that many barrels that are hammer forged and especially those which use polygonal rifling do not leave the kind of machining marks of barrels that are broached or button formed. Bullets fired from weapons such as the Glock or HK USP are essentially indistinguishable out of the box. So aside from the each in switching out a barrel or modifying the identifying marks, and the deformation that occurs on a bullet that contacts a hard surface, some arms don’t even lend themselves to this kind of analysis. What you see on the court shows where the forensic ballistician presents a “perfect match” between a recovered bullet and one fired from the suspect’s weapon is at best an exaggeration in the best of circumstances.
Identifying the getaway vehicle based upon tire tracks that indicate that it is only one of two cars built in the 'Sixties with both independent rear suspension and Posi-Traction, on the other hand…that is some solid and incontrovertible forensic testimony right there.
Stranger
Honestly, that data wouldn’t amount to much in the REAL world.
The ballistics data for each round is a bit different.
For a few hundred rounds out, the entire character of the ballistics have changed.
So, unless you’re in a state that requires such idiocy, the data could rather quickly turn into nothingness, save wasted server space.
Or even more simply, CSI is, yet again, full of cattle cookies.
Though they DO occasionally serve up pigeon pellets…
Now, if you’re a hit man, you’d know that you dump the gun, period. More thrifty types would replace barrel, extractor and firing pin. Not realizing some OTHER parts leave THEIR mark…
Semi-automatic barrels are, typically on or around the breech. That number matches the one on the slide and the one on the frame if it’s original.
Most certainly doesn’t, but when the investigator comes knocking at your door(Bob) and questions you about the pistol that you purchased from the LGD and you start in about how it was stolen and he is recording your every word then retrieves the police report that describes …
Well you may be off the hook in criminal court, but now you have to travel to Detroit to answer in the civil system.
Short answer, You don’t want to be Bob in Kali!
Why? It’s not against the law to have a gun stolen.
Unless the purpose of your scheme is to frame the other person rather than to kill the victim, you’re adding an unneeded complication. Just police your own brass and be done with it.
Use a throw-away revolver. No brass flying about.
Although I think most of the forensic evidence could be seriously compromised by a rat-tail file and 30 seconds. After the shooting, just run the file over the firing pin and down the barrel a few times, then go to the range and plow through a few hundred rounds. Police and dispose of your own brass, of course. You will have so altered the pattern on the firing pin and scratches on the barrel as to make them fairly useless in court.
Yeah it is pretty fast and easy to unscrew the old barrel and screw on a different one. If the police do a ballistics test on the new barrel, that would prove your innocence and eliminate you from being a suspect.
Also, people who shoot revolvers, do not leave their spent casings behind, so the only thing that the detectives will have is the fired bullet from a barrel that does not exist anymore and which therefore provenly does NOT match the barrel of the murderer.
Any smart person that wanted to murder would do this, leave spent casings from someone else’s gun implicating somebody else, as well as the murderer putting on a new barrel to prove that the murders gun was not used. You got the police both coming and going the wrong way. Doing both of these things would really help to almost insure that the murderer would go free.
- Seriously, people, stop adding needless extra steps to your schemes. There’s such a thing as being too clever by half.
- Also stop advertising your clever plans on the 'Net.
- You know something? Nobody commit any felonies without running 'em by me first.
Originally Posted by jtgain
Plus it would be a nice way to pin a murder on someone else. Let’s say I have a 9mm. I could hang out at the range and the next time a guy is firing a 9mm, I could pick up his brass. Then, when I commit my murder, I take an extra two seconds to pick up my brass, throw down his, and BAM, ballistic fingerprints link him to the murder…
It is not a** “complication”** at all. It is a** “diversion”**, and a VERY effective diversion.
1.Cops are basically lazy, and if they have a suspect who owns a gun which matches the crime, those lazy cops are not going to lift a finger to go after somebody else, esp since going after somebody else means that the best evidence of spent casings found at the crime scene could not be used by the prosecution at all.
- Furthermore, most prosecutors are not out to clear suspects nor to destroy evidence, rather, they are out to convict.
Pinning the crime on somebody else, “clears” the crime as far as the police are concerned since they can record an arrest as a solved crime. It also makes the prosecutors job very easy to get a conviction.
- Third, the politicians will love to convict the innocent man since it would prove that their spent casing data base was a great idea and would use this case as an example to get re-elected. Everybody wins by convicting the wrong guy if we had a manufacturers database.
It will not “prove your innocence.” It will fail to prove your guilt. BIG difference!
Originally Posted by Susanann
Yeah it is pretty fast and easy to unscrew the old barrel and screw on a different one. If the police do a ballistics test on the new barrel, that would prove your innocence and eliminate you from being a suspect.
No difference at all, same thing. The police will leave you alone and go after somebody else after their own forensics experts prove that the bullets could not have come from your gun. Just ask Lawrencia “Bambi” Bembenek .