How traceable are bullets?

[Fosbery]

Is it possible to link a bullet to a specific gun, other than simply matching calibers? For instance, from the rifling marks on the bullet?

I'm pretty sure it's not, but wanted to check.

Is there such a thing as a ballistics database in the US or certain states?

 

[Kleanbore]

It is.

 

[Blackbeard]

They match rifling marks by comparing two bullets - one found at the scene and a test round fired from a specific gun -- if they match then they know the same gun fired both bullets. I'm not aware of a rifling marks database that would let you "look up" what gun fired a given bullet. If there were such a database it'd be useless if the gun's owner ever changed barrels.

 

[Sam1911]

Is it possible to link a bullet to a specific gun, other than simply matching calibers? For instance, from the rifling marks on the bullet?

To a degree, yes. If a fired bullet is recovered at a crime scene (for example) that is still in good enough condition to observe the rifling marks, it can be compared to a bullet fired from a specific firearm to see if the rifling marks match. Like finger-printing, this is more of an art than a science, and it depends on matching the number of similarities between the marks on the two bullets to establish a probablility that they were fired from the same gun. There is no "certainty" to it.

Several problems exist with the technique: For one, the rifling in the bore of a firearm changes as it wears. The more firings take place between the two test bullets, the less alike the marks will be = probability goes down. As pointed out, if the owner replaces the barrel, all bets are off.

The bigger problem comes in simply having test material. To do this, you'd need a recovered bullet in fairly decent condition. The more smashed/deformed the slug is, the harder identification will be (even less probability of a match). And, you need to have the rifle or pistol you suspect fired the round in hand so you can run the control test and recover the comparison bullet.

Simply having the recovered slug from a crime scene gets you little beyond knowing the caliber, weight (assumed, from what's left), and possibly the make of gun it was fired through (Polygonal or cut rifling? Number of lands & grooves, etc.). Without a suspect in mind, and his gun in custody to test, there's no way to use the fired slug as a "signature" to ID the shooter, or even the owner of the gun.

Is there such a thing as a ballistics database in the US or certain states?

No. Some states (MD) have (or had) maintained "ballistics fingerprint" records on all handguns sold. But, to my knowledge, these only kept fired cartridge cases -- not recovered bullets. The idea being that the fired cases bear the markings of the firing pin, extractor, ejector, and whatever impact marks the gun makes on the case as it cycles. Then the cases on file could be compared against cases recovered at crime scenes. The same issues of uncertainty apply to this as to the bullet "fingerprinting," of course.

Information I've read indicates that many millions of dollars have been spent to build and maintain these databases/archives, and they've yet to be used conclusively in ONE criminal trial.

-Sam

P.S. -- Fortunately, on television, this is a valuable and reliable set of tests that puts the bad-guy behind bars in 30 minutes or less, every week! ;-)

 

[chuckusaret]

I'm not aware of a rifling marks database that would let you "look up" what gun fired a given bullet. If there were such a database it'd be useless if the gun's owner ever changed barrels.

I thought Maryland required a spent bullet be provided to the state by the gun manufacturers on all guns sold in the state. I also heard that this program, the cost is in the millions per year, had not assisted in solving any shooting cases.

Could someone from Maryland reply please or has anyone else heard of this requirement. I attempted to find the Md. law but to no avail.

 

[loadedround]

Chuck: I my memory serves me correctly, Maryland quietly dropped dropped this law a short time ago. It was costing them many millons of dollars yearly and had not yet solved any crime, nor lending any clues to crime. Just another "feely good" liberal law that never worked.

 

[heron]

It was just a few nights ago, on CSI Miami, they took a bunch of tiny, tiny bullet fragments from some victim's body, and scanned them, and a computer put them all together like a jigsaw puzzle, and they got a match . . . and I think those people actually DO have a database of rifling marks!

well, hey, it must be true, it was on TV!

<snark off>

 

[nitetrane98]

Several problems exist with the technique: For one, the rifling in the bore of a firearm changes as it wears. The more firings take place between the two test bullets, the less alike the marks will be = probability goes down.

Just to illustrate that, I heard somewhere that the Mannlicher Carcano rifle used to kill JFK has been fired so many times after the fact by the "experts", trying to determine if the rate of fire could be matched etc, that it now could not be proven that it was the gun used to kill JFK based on ballistic matching.

 

[lebowski]

I believe NY (not sure if it's NY State or NYC) has or had a program for ballistic fingerprinting. My understanding is the program was a massive failure - they spent millions of dollars, fingerprinted tens of thousands of firearms, and the program has helped solve exactly zero crimes.

I read about it on wikipedia, so take that for what it's worth. I can't find the article now.

 

[bigalexe]

How traceable are bullets?

Well if the bullets have a bit of Phosphorus or other incendiary in the back of them they are immediately traceable to the source provided you are on the right angle.

 

[isp2605]

There is a national database but mostly of fired cases. It's been operational for about 15 yrs. It works sort of like AFIS which is the fingerprint database. Fired cases are entered into the database. Then cases recovered from a crime scene can be scanned into the system and the computer will check that case with cases in the system. What that will do is link a gun used in Shooting A with Shooting B.

 

[moooose102]

yes, it is possible to match a bullet to a gun, providing they have the gun to compare it to. but, it is also possible to alter the barrel so it shoots a bullet so it no longer matches how it used to. it is not all that hard on a pistol, but a rifle would be much more difficult. i will not go into it, because i do not want to give anybody directions, but a little imagination would go a long way. i had never thought about it until i looked at the inside of one of my pistol barrels with an eye loupe. do that, and it will almost become self evident on what and how to do it.

I believe NY (not sure if it's NY State or NYC) has or had a program for ballistic fingerprinting. My understanding is the program was a massive failure - they spent millions of dollars, fingerprinted tens of thousands of firearms, and the program has helped solve exactly zero crimes.

just like microstamping! a horrible waste of time and money for no real purpose other than making ammo so expensive it will deter shooting all together.

 

[Sam1911]

I thought Maryland required a spent bullet be provided to the state by the gun manufacturers on all guns sold in the state.

I lived in MD up until about 3 years ago, and there was only the fired CASE requirement, nothing about the bullets. And only for handguns.

Maryland quietly dropped dropped this law a short time ago. It was costing them many millons of dollars yearly and had not yet solved any crime, nor lending any clues to crime.

I had heard that the MSP was lobbying to have this killed off as well. The number $20 million keeps floating through my memory. That was some years ago, though. I believe that the "ballistic fingerprint" data had been submitted as evidence in something like 4 criminal trials, but was conclusive, instrumental, or enlightening in none of them. Seems the MSP believes they could use $20 million (or whatever) elsewhere and aren't getting much help for the money.
-Sam

 

[Sam1911]

There is a national database but mostly of fired cases. It's been operational for about 15 yrs. It works sort of like AFIS which is the fingerprint database. Fired cases are entered into the database. Then cases recovered from a crime scene can be scanned into the system and the computer will check that case with cases in the system. What that will do is link a gun used in Shooting A with Shooting B.

Do you know where these cases are coming from? Is this a database of cases collected at crime scenes that are then held on file for future matching?

The manufacturers of firearms are certainly not sending sample cases from every gun they make to the government.

Please provide a link that explains this more clearly. Considering that the government doesn't maintain a database of where guns go or who buys them, they certainly aren't "finger-printing" them all, either.

-Sam

 

[Sam1911]

http://www.ocshooters.com/Reports/cobis/ibis.pdf

This is a report on ballistic fingerprinting by MSP's Forensics Sciences Division. A great read (well the first few paragraphs, which is as far as I got through it).

Seems they consider it too flawed to proceed with and completely worthless as far as producing "hits."

They cite New York State's "sister program" which is costing $4 million A YEAR and has not yet produced A hit.

-Sam

 

[isp2605]

Do you know where these cases are coming from? Is this a database of cases collected at crime scenes that are then held on file for future matching?

Most are from crime scenes, recovered firearms, evidence, etc. I believe states that required fired cases were also submitting them to the database but since I never worked with states like Maryland on any cases I don't know what they were submitting.

The manufacturers of firearms are certainly not sending sample cases from every gun they make to the government.

Nope. Like I said it's similiar to AFIS. Not every person in the US is fingerprinted and put AFIS. Same with Drugfire. It's data than comes into the system.

Please provide a link that explains this more clearly. Considering that the government doesn't maintain a database of where guns go or who buys them, they certainly aren't "finger-printing" them all, either.

Do a search on "Drugfire". That's what the FBI called their database. ATF also had a similar database but I can't recall the name of it. I only used Drugfire on my cases.

 

[eye5600]

I've always wondered what would happen if you took 50 sequentially manufactured guns off the line from a good manufacturer (e.g. Colt or S&W) and fired 2 bullets from each, then mixed up the 100 bullets and let a firearms examiner try to pair them up. Public statements on firearms ID suggests that they could be sorted out with no error or minimal error, but more candid comments suggest not.

Of course, in the real world from law enforcement, it can weigh pretty heavily even if the ID only goes to the number of lands and grooves and a match to the construction of the bullets still in the gun. It's like getting the make and model of the car, but not the plate number.

 

[JimmyN]

I have gotten several new firearms that came with a small manilla envelope that contained a fired case from the factory. The envelope was marked with the date, caliber, model and serial # of the handgun. I don't know if they still do, but all new Glock's used to come with a factory fired case.

In VA you received the envelope and fired case with the new firearm, since it serves no purpose, other than a record of when the factory built and test fired your new gun. But if you are in Maryland the FFL dealer that sells you the new firearm turns that envelope over to the State Police for their spent case database. Or at least that is the way it used to work.

 

[41022collector]

Various forensics labs have data bases of bullets and firearms used in crimes. new York and a cpl other states require a certified shot round and the bullet and case kept on file for all firearm sales.

Lead inside of a barrel can be matched to a specific bullet. The bullet lead can be matched with company records of chemical make up. A bullet with decent rifling can be matched to a type of firearm and one the firearm is found can be matched to that bullet.

Ballistics forensics is a wide field and many aspects of it. The FBI prob has the most extensive searchable by LEO request data base in the world. Starting 2010, there will be many matching characteristics of both firearms and ammo. Micro Stamping of firearm serial numbers on firing pins and bolt/breech faces. lead and other metals in bullets will soon have ID tags in them, the powders used will also have id tags. Shell cases will have NON wipable surfaces to capture finger prints.

Regards,
Mike

 

[isp2605]

Public statements on firearms ID suggests that they could be sorted out with no error or minimal error, but more candid comments suggest not.

It's pretty simple really as long as the items being tested are in useable condition. It's not rocket science. It's nothing more than tool mark identification when comparing things like screwdriver pry marks or any other metal to metal markings. No metal is completely 100% smooth unless it undergoes a lot of polishing which is not the case in firearm manufacture. Such polishing is only done for extreme scientific uses. Any scratches or imperfections on an item when rubbed against another item will leave impressions. In the case of a firearm the barrel with it's imperfections are harder than the bullet materials. When the bullet rubs against the barrel the imperfections on the barrel are transferred to the bullet. Pretty simple then to compare.

 

[Sam1911]

Public statements on firearms ID suggests that they could be sorted out with no error or minimal error, but more candid comments suggest not.

It's pretty simple really as long as the items being tested are in useable condition. It's not rocket science. It's nothing more than tool mark identification ... When the bullet rubs against the barrel the imperfections on the barrel are transferred to the bullet. Pretty simple then to compare.

In a perfect situation, yes. But take the recovered bullet out of an oak tree or plaster wall, where it is highly deformed and the surface it embedded into has caused extensive additional marking and things get a lot harder. (Like you said, a usable sample.) As less and less of the bullet's exterior surface is left pristine, fewer points of comparison can be reliably made. And when you take those few points and compare them to those on bullets fired by two different examples of identical guns, the "paternity test" gets a lot more inconclusive. Put them through a pistol such as a Glock that uses polygonal "rifling" and I would imagine it's yet another step harder to differentiate which gun fired the sample bullet.

So, it's not rocket science in that it isn't all that complicated. But the results are not universally conclusive, either.
-Sam

 

[Sam1911]

Starting 2010, there will be many matching characteristics of both firearms and ammo. Micro Stamping of firearm serial numbers on firing pins and bolt/breech faces. lead and other metals in bullets will soon have ID tags in them, the powders used will also have id tags. Shell cases will have NON wipable surfaces to capture finger prints.

Which legislation is this that will bring all this new technology? Is there something on the books that will make this reality next year? I keep hearing rumors of legislation being proposed, but it's always shot down as impracticable.

Last I heard we were a LONG way from any of those being possible, so if it will be federally mandated, please let us know!

-Sam

 

[highorder]

I've always wondered what would happen if you took 50 sequentially manufactured guns off the line from a good manufacturer (e.g. Colt or S&W) and fired 2 bullets from each, then mixed up the 100 bullets and let a firearms examiner try to pair them up.

They would (honestly, objectively) NOT be able to tell you anything.

Lead inside of a barrel can be matched to a specific bullet. The bullet lead can be matched with company records of chemical make up.

You DO know that has been debunked, right?

All this stuff falls into the same catagory as the polygraph.

It's sham science used as an interrogation tool, or a case-maker in court.

 

[Sam1911]

Lead inside of a barrel can be matched to a specific bullet..

I've not heard of many folks getting shot these days with unjacketed lead ammo... And, even if we're dealing with JHPs or FMJ, how would knowing that one gun fired the kind of bullet (jacketed) that was used in a crime (or even the brand of bullet) make for a good prosecution, when there's only a handful of manufacturers and probably 7 out of any 10 guns tested would have copper fouling from either one of them you'd pick?

The bullet lead can be matched with company records of chemical make up

Cite, please? Yes, I know they do it on TV. I want to see a real-world example of a forensics lab using mass spectrometry to link a bullet to a specific manufacturer by alloy composition. And, again, if there's under 10 very common bullet manufacturers, and even allowing that their alloys are consistent enough and distinct enough to repeatably tell one from another (which I doubt), how does this help the prosecution?

Prosecutor -- "Your honor, due to the distinct chemical signature of the fouling in the defendant's gun, we now can conclusively prove that he has fired the same ammo as the bullet which was used to murder the victim! A kind of full-metal-jacketed ammunition known as Winchester "White Box."

Defense -- "Uh, your honor, every gun in the state has had Win. White Box through it..."

-Sam

 

[isp2605]

In a perfect situation, yes. But take the recovered bullet out of an oak tree or plaster wall, where it is highly deformed and the surface it embedded into has caused extensive additional marking and things get a lot harder

The recovered bullet doesn't have to be in perfect condition. I've had bullets matched recovered from trees, after going thru wall board and imbedding into 2X4s, after going thru car bodies and interiors. As long as the rifling is completely deformed it can usually be a viable specimen. It does take a whole lot of material.

Put them through a pistol such as a Glock that uses polygonal "rifling" and I would imagine it's yet another step harder to differentiate which gun fired the sample bullet.

One of the internet falacies being spread was bullets from Glocks can't be traced to a specific firearm because of the Glock's polygon bore. Not so. Any metal on metal transfer is enough. There's no rifling on screwdrivers and prybars and we make cases everyday on those tool marks. And barrel-bullet transfer is nothing more than a tool mark. We don't make every case where a pry bar is used either but that doesn't mean it's useless technology. It's not like TV and CSI.
The polygon bore "theory" is the same as the old story of Glocks can't be seen on airport xray machines.