Loopholes in Ballistic Fingerprinting

[LibraPMC]

In movies and TV shows, police manages to locate the specifics like caliber to specific gun model used in the crime just by examining the collected bullet.

But in reality I think it is way too easy for thinking criminals well aware of ballistic fingerprinting to manipulate the system. Let's say criminal uses 357 sig for the crime, collects 357 brass and shatters the same number of fired 9mm brasses instead. Investigators, since two caliber have same diameter(.355), they will be unable to locate the difference. Well penetration and terminal effect can be seen but there is still +P+ 9mm rounds. This is only a small portion of possible loopholes I came up with. Does LE have alternatives for them? Anyone LEO here?

 

[M-Cameron]

In movies and TV shows, police manages to locate the specifics like caliber to specific gun model used in the crime just by examining the collected bullet.

But in reality I think it is way too easy for thinking criminals well aware of ballistic fingerprinting to manipulate the system. Let's say criminal uses 357 sig for the crime, collects 357 brass and shatters the same number of fired 9mm brasses instead. Investigators, since two caliber have same diameter(.355), they will be unable to locate the difference. Well penetration and terminal effect can be seen but there is still +P+ 9mm rounds. This is only a small portion of possible loopholes I came up with. Does LE have alternatives for them? Anyone LEO here?

movies and TV have the liberty to ignore facts and make up science......Real life isnt so lucky.

now im no CSI.....but ide imagine it would be pretty difficult to trace an intact bullet to a specific make and model of gun, never mind one thats been deformed

now if you have a suspect gun, ide imagine you could probably match a bullet fired through that to a bullet recovered from the scene.....but even then that might be difficult to prove beyond a reasonable doubt.

 

[svtruth]

What about a revolver, firing frangible bullets?

 

[hso]

TV is not reality. The "CSI effect" both hurts and helps forensic scientists when providing testimony in trials because it creates completely unrealistic expectations on the part of jurors. Great recent piece I saw this or last week on that.

 

[Quiet]

Last jury selection I was in (for robbery & murder); the judge had a speech about the "CSI effect", how what you see on TV/movies doesn't exisit in real life and if you can't except that, then you won't be selected for the jury.

 

[Loosedhorse]

Sometimes yes, sometimes no. Caliber, number of lands and grooves, rifling pitch (rate of twist), depth of rifling, hexagonal or polygonal rifling, LH or RH twist, etc. can narrow you down to one or just a few brands in some cases, and then to one family of guns in that company (for example, Colt Police Postive/Colt Detective Special).

However, ballistic fingerprinting is different.

It is the idea that the unique tool marks on the chamber and breachface of each individual firearm will allow the police (who will keep a digital scan of an "exemplar" fired case from every gun sold) to (uniquely, and without error) match a found fired case to the gun that fired it.

As we know, the ballistic fingerprinting registries of Canada and Maryland had not contributed to solving a single crime.

It would be interesting to know how many errors such a registry would be capable of: how many times it spits out multiple matches to a found case; or the wrong match.

Ballistic fingerprinting is easily defeated by polishing the breachface and chamber. So, that would have to be regulated: if it was done, a new exemplar would have to be registered with the police. Same if you buy an aftermarket barrel. And after a lot of rounds, the tool marks would start to wear, so you'd need a new exemplar, what, every year for each gun?

Personally, if ballistic fingerprinting ever became universal, I would video myself polishing the chamber and breachface, date it, and file it with my lawyer; so if a random check ever came back to my gun, I could show that it couldn't possibly be my gun. Of course, they'd probably have made such altering a crime, on a par with erasing a serial number.

It is a scam.

What about a revolver, firing frangible bullets?

Remington used to make Accelerator rounds: .30 cal rounds using a .223 bullet in a nylon sabot. I think they got heat from LE because the bullets would have no rifling marks; in any case, they are no longer made.

 

[LibraPMC]

^ Well that's my point!
If polishing feed ramp, changing ejector or barrel swap to aftermarket parts easily defeat the system, why is it referred to all the time? Was it ever practical?

 

[Loosedhorse]

why is it referred to all the time?

Because it is technicool jargon, which few people understand. That gives fiction writers a lot of leeway to claim it can do things it can't.

And because (it is my suspicion that) most Hollywood types are ferverently anti-gun, leaving the impression that ballistic fingerprinting is necessary to solve crimes would matter to them.

Since there is no such suggestion of its usefulness in reality, they write fiction about it.

 

[LibraPMC]

Because it is technicool jargon, which few people understand. That gives fiction writers a lot of leeway to claim it can do things it can't.

And because (it is my suspicion that) most Hollywood types are ferverently anti-gun, leaving the impression that ballistic fingerprinting is necessary to solve crimes would matter to them.

Since there is no such suggestion of its usefulness in reality, they write fiction about it.

Oh I see... Then how does the police trace gun crime scenes to the shooter? If it isn't CSI stuff and finding match in database, gun crime should be no different from other types of crimes in terms of investigation easiness.

 

[Skribs]

When I openned this thread, I was thinking of the idea of microstamping the firing pin. Criminal grabs brass at local pistol range that has been stamped by a legitimate user, uses his gun which either predates the requirement or has had the microstamp filed off, and the only stamp is from the guy who legitimately shot the gun at the range.

 

[rodregier]

re: Rem Accelerators

They were alleged to have poor accuracy, which didn't help their sales either. You can still buy .22/30 sabots and handload. The Sabot will still retain rifiling marks, it's just that the projectile won't.

http://www.sabotreloadingpro.com/

http://www.eabco.com/reload02.html


A paper-patched bullet probably would not have any ballistics markings either. Getting the right projectile or bore size to make that work for a jacketed projectile would be challenging but not impossible.

 

[Warp]

Movies/TV shoes outright lie. Often I believe they have an agenda behind it. I refuse to watch them. My wife is not allowed to watch CSI anymore (dead serious)

 

[Warp]

When I openned this thread, I was thinking of the idea of microstamping the firing pin. Criminal grabs brass at local pistol range that has been stamped by a legitimate user, uses his gun which either predates the requirement or has had the microstamp filed off, and the only stamp is from the guy who legitimately shot the gun at the range.

The stamp would be on the primer, not the case, would it not?. I also doubt most criminals would be able to pick up the case and reload it anyway.

Microstmping is some freaking bullcrap anyway. I see no way that will pass. If it did I would be buying only used guns without them/only using non reloadable rounds in aluminum or steel at the range/collecting all brass (easiest with wheelgun)

 

[tyeo098]

The stamp would be on the primer, not the case, would it not?. I also doubt most criminals would be able to pick up the case and reload it anyway.

Microstmping is some freaking bullcrap anyway. I see no way that will pass. If it did I would be buying only used guns without them/only using non reloadable rounds in aluminum or steel at the range/collecting all brass (easiest with wheelgun)

No, but he can sprinkle a few of them around the crime scene.

 

[OldmanFCSA]

OK - so I have a warped sense of humor ...............

I always pickup my range brass as a habit and to see what others may be shooting. Afterwards I sort to keepers and junk pile. Once I had a can of steel-cased 7.62X39 empties that I was trying to decide what to do with ..................

A few years ago, Minneapolis was having a major problem with drive-by shootings .............

With too much time on my hands, and being near 4th of July, I was thinking ...........

Dump the brass on the street at night, drive around corner, light off a 500 ct package of BlackCats, and wait for a major crime scene investigation. As in the movies, a numbered marker by every case found, several hundred or more ...............

Just my luck - my fingerprints are still on the cases !!!!!!!!!!!!!!

Ask me how I got caught pouring a LARGE box of Tide down the hole of a new water-fountain the night before it was to be celibrated???? Good clean fun, right Officer ???

 

[Dueling1911s]

just pick up a 357 sig barrel, extractor and firing pin at a gun show with cash. drop some 9mm casings around from the range. swap the parts out afterwards and dump them in a mcdonalds bag you've had laying around your backseat for ever and put in a random public trash can on the way home

 

[Skribs]

Oldman, that's a great story.

I've had similarly mischievous ideas for pranks that are definitely illegal but totally harmless, but I've never actually acted on them. Of course, they aren't gun related, so no point going too far OT..

 

[Geckgo]

A database, with everyone's guns in it??? Hmmmm, yea I don't like that idea. POs need to work for a living, just like the rest of us.

 

[Loosedhorse]

Then how does the police trace gun crime scenes to the shooter?

They usually don't.

What does in some cases happen is a used bullet (or perhaps case) is recovered at a crime scene, in good enough shape to examine in detail. A candidate gun is then identified (by search of crime scene or of a suspect's belongings) and test-fired. It can then be determined if the markings on the bullet or case from the test is similar enough to the one in evidence to conclude that that same gun produced the bullet or case in evidence.

What one typically sees on TV is some large bullet database (from prior crimes), with the computer producing a match to the fired bullet or case in seconds.

 

[Owen Sparks]

None of this technology will work if the police don't recover the gun. If the shooter simply drops by to visit Mom on the way home and hides the gun 'off warrent' he will have little to worry about and can recover it later.

 

[Warp]

I've had similarly mischievous ideas for pranks that are definitely illegal but totally harmless

In my opinion people are a bit too quick to claim something has "totally harmless". Obviously the cases/firecracker/drive by situation mentioned did not directly harm anybody. However, it was not only reasonbale to assume but intended to utilize a lot of manpower from local law enforcement. This is a bad thing that could very well lead to harm that would not have otherwise occurred. Taxpayers spending moeny on overtime for the invesitagation is, IMO, harm. LEOs not being about patrolling, deterring, reacting to crimes, etc, becasue they are tied up at the scene of the prank is, IMO, harm.

 

[Panzercat]

I always got a kick out of the idea of running a round out of two separate guns. Fire into a non destructive medium to be recovered, then use it in your second firearm as the operable weapon. Reality says you probably don't even need to get that complex. You could probably mark the round up before chambering through some mundane method to throw off the fingerprinting.

 

[OldmanFCSA]

OK - so I have a warped sense of humor ...............

I always pickup my range brass as a habit and to see what others may be shooting. Afterwards I sort to keepers and junk pile. Once I had a can of steel-cased 7.62X39 empties that I was trying to decide what to do with ..................

A few years ago, Minneapolis was having a major problem with drive-by shootings .............

With too much time on my hands, and being near 4th of July, I was thinking ...........

Dump the brass on the street at night, drive around corner, light off a 500 ct package of BlackCats, and wait for a major crime scene investigation. As in the movies, a numbered marker by every case found, several hundred or more ...............

Just my luck - my fingerprints are still on the cases !!!!!!!!!!!!!! This statement was meant to show how I would be caught IF I did it.




Ask me how I got caught pouring a LARGE box of Tide down the hole of a new water-fountain the night before it was to be celibrated???? Good clean fun, right Officer ???

To: WARP

Never did this - just was thinking about it.
And how it would relate to original posting.

But you guys did post a lot of good ideas for criminals to get-away-with-it.

 

[Neverwinter]

A database, with everyone's guns in it??? Hmmmm, yea I don't like that idea. POs need to work for a living, just like the rest of us.

I don't think that arguing from the position that police should have to work harder to provide justice is a valid one. Arguing about the investigative value of the database relative to the costs makes more sense.

The greatest criticism of anything we buy/create is whether the value added by its existence is worth the cost. Does it add investigative value?

Misuse in the court system can be fixed through decent jury selection and a defense attorney's expert witness selection.

Sent from Tapatalk

 

[Dueling1911s]

They usually don't.

What does in some cases happen is a used bullet (or perhaps case) is recovered at a crime scene, in good enough shape to examine in detail. A candidate gun is then identified (by search of crime scene or of a suspect's belongings) and test-fired. It can then be determined if the markings on the bullet or case from the test is similar enough to the one in evidence to conclude that that same gun produced the bullet or case in evidence.

What one typically sees on TV is some large bullet database (from prior crimes), with the computer producing a match to the fired bullet or case in seconds.

dont some communist states require you to register the fired shell casing that comes with most guns. would be a database from

i love the sticker on my xd45. "not legal in the state of california"