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bullet time stamp

Police bullets that know when and where they were fired
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If you watch procedural cop shows, there's always these questions about bullets - who shot what, how many, who shot first.

What if the bullet could tell you?

Now, criminals, they won't cooperate. But law abiding citizens and police will.

How about a system that lets you know when and where a bullet was fired?

Both the bullets and the guns could be altered to arrange this.

First, the lead part of the bullet - the slug - could be made special, including a combination of two isotopes or other types of metals. These would be trace elements, and the type included could tell you which slug was which. If used in a handgun, you'd only need 100 or so different combinations, just to rule out two different bullets being misidentified, although having a greater breadth of combinations would help.

Next, the casings would also have identifying marks on them, so that each one was unique. Those markings could be read by the weapon as the bullets enter the chamber from a clip. This would not likely work readily in a revolver, but maybe there's a way. The energy from the bullet could be used to power the internal system (therefore, no battery needed), which would track the bullet number in a memory chip. A low power battery would be used to keep a clock running. Any interruption would be noted.

The serial number of the bullet, noted at the time the bullet is fired, would include info about the composition of the slug. And maybe its metal composition could even help you find the bullet.

But so long as the slug and casing were found, you could confirm the location of the slug, approximate the location where the shot was fired, and then know exactly when the shot was fired.

In addition, if a GPS system were either in the gun, or connected to say a smart phone or other police device, the location could also be made more accurate by the system.

Could also work without the slug being special, so long as the weapon could read a unique serial number on the back of the casing.

simpleknight, Jan 09 2014

Smart Dust http://www.cnn.com/...smart.dust.sensors/
related [Voice, Jan 09 2014]

bullet time http://en.wikipedia.org/wiki/Bullet_time
As mentioned in an annotation. [Vernon, Jan 09 2014]

Training that tracks shot by shot https://www.cubic.c...efense-Applications
Criminals won't wear the tracking vests, but in a training situation this works. The shot of blank or live round triggers an aligned laser [popbottle, Jan 12 2014]

Nano RFID http://www.engadget...oparticle-barcodes/
Looks like one part now exists [simpleknight, Jun 09 2014]


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Annotation:







       This would also be helpful in determining whether a hunter took his shot within legal hunting hours (since deer are most active around dawn and dusk, which can be infuriating). [+]
Alterother, Jan 09 2014
  

       This would help a LOT with preventing ammunition theft. Imagine bullets no criminal wants. Depending on how integrated it is with the firearm it may help prevent gun theft as well.   

       Smart dust is a related idea. Sprinkle a little onto your item and it's all but impossible to ever get it all out making tracing easy.
Voice, Jan 09 2014
  

       Some ammunition manufacturers (led by Hornady*) are laser etching serial numbers into the tail of their bullets, which helps identify end-users even more specifically than telltale chemicals in the powder. In addition to being inaccessible until the round is fired, the tail of a FMJ bullet nearly always survives impact.   

       It occurs to me that one could deliberately remove the numbered bullet and load it into another casing, but in that case the mismatched telltales and serial number would be an immediate giveaway that would narrow the search parameters to people with hand loading knowledge and equipment.   

       * and vehemently opposed by Black Hills...quelle suprise...
Alterother, Jan 09 2014
  

       What, this Idea is not about putting a stamp on a bullet while it slowly goes by, during "bullet time"?
Vernon, Jan 09 2014
  

       //It occurs to me that one could deliberately remove the numbered bullet and load it into another casing, but in that case the mismatched telltales and serial number would be an immediate giveaway that would narrow the search parameters to people with// access to Wikipedia and Amazon.   

       If criminals can figure out how to clandestinely make crystal meth, I'm pretty sure they can figure out how to operate a kinetic bullet puller.
ytk, Jan 09 2014
  

       very small electronic chronometers are dirt cheap. All you need is one connected to a ROM chip that records the time. When the chronometer stops (because you didn't select one that's resistant to huge G force), you will know the time of firing by looking at the last ROM dump.
bs0u0155, Jan 09 2014
  

       // , I'm pretty sure they can figure out how to operate a kinetic bullet puller. //   

       Agreed, but getting the bullet into another casing is trickier. It's not juggling space shuttles, but handloading is a skill that takes patience, practice, financial investment, and book-larnin' (and it's boring as all fuck); it truly is not a mainstream hobby. At a rough guess, I'd say 1 in 10 of my fellow hardcore gun nuts load their own (the rest just mooch off of those who do).   

       Thus, using hand-loaded ammo in a crime is a bad idea, because while they may not be able to determine who loaded the rounds, it _will_ send the police looking for a dedicated firearms enthusiast rather than just any violent criminal with a gun, and they can also start interviewing handloaders, narrowing their search further by the caliber and type of bullet, the shape of the brass, the composition of the powder, and a gazillion other things that make each handload unique. I can tell at a glance the difference between my loads and those of four other handloaders in my extended community, and I'll happily spend as long as anyone wants to listen explaining how and why mine are the best. So will the other four guys, which is why it wouldn't the cops long to find out who made the cartridge, and it won't be long after that when they find out who fired it.
Alterother, Jan 09 2014
  

       Actually, scratch that. There are electronics rated to survive in artillery shells including those that can direct the shell.   

       A simplified version would just be a chronometer and a g recorder. You could then work out time of firing and the time/G profile of it's journey. You could probably infer a lot about what the bullet hits by the G.
bs0u0155, Jan 09 2014
  

       //It's not juggling space shuttles, but handloading is a skill that takes patience, practice, financial investment, and book-larnin'//   

       I used to hand-load (mostly .357 Mag and .308 Win). Still have the equipment in my garage somewhere. But taking a bullet out and putting it back in isn't really that difficult, even without a press.   

       Remember, you're not having to deal with case trimming, priming, resizing, measuring powder, or anything more complicated than removing a bullet and putting it back in the case—which can be done without so much as a single reloading die. A 9mm round will headspace and fire just fine without re-crimping the case mouth.   

       And there's really no way to tell ballistically that a bullet has been removed and replaced before firing. Yes, it would be a bad idea to murder someone with my custom low-charge moly coat competition .357 rounds, but that's not what we're talking about here. If criminals discover that there's a real benefit to switching bullets around before loading them, they'll find a way to do it.
ytk, Jan 09 2014
  

       Why do criminals use anything other than shotguns? If I were involved in street level turf wars, having all your guys using shotguns would undermine any ballistics evidence. Or can you trace a shotgun?
bs0u0155, Jan 09 2014
  

       Ever try to walk down the street carrying a concealed shotgun?
ytk, Jan 09 2014
  

       the old violin-case trick from the 30's should come into place here. Or is being seen with a violin case worse than death for a modern gangster?
bs0u0155, Jan 09 2014
  

       // taking a bullet out and putting it back in isn't really that difficult, even without a press.    //   

       It is if you're putting it in different brass with different powder; then you most likely will be trimming, sizing, pouring, and priming. Removing the bullet and then putting it back in the same casing for forensic misdirection purposes makes no sense, even if you switch the powder.
Alterother, Jan 09 2014
  

       // Or can you trace a shotgun? //   

       Yes and no. Projectiles fired from a smooth-bore shotgun cannot be matched to that specific gun, but the tool mark and firing pin imprints left on the brass part of a spent shell casing can be matched.
Alterother, Jan 09 2014
  

       Eject the shells inside the car during a drive-by. Check. Education's a marvelous thing.   

       (rushes off to pistol ammunition with magnesium driving rings... all your rifling marks burned away... mwahahahaha)
bs0u0155, Jan 09 2014
  

       //It is if you're putting it in different brass with different powder; then you most likely will be trimming, sizing, pouring, and priming. Removing the bullet and then putting it back in the same casing for forensic misdirection purposes makes no sense, even if you switch the powder.//   

       I think the idea ytk is getting at is that a criminal in the supply chain switches bullets between casings of two boxes in a batch of serial-numbered ammo, sells one to a mark (ideally, someone who gets through a lot of ammo) then sells the other one as "alibi ammo" to a hitman.
Loris, Jan 10 2014
  

       Erm, something very lightweight technology-wise, like a slow version of silver nitrate on the back of the bullet, as it's going from a dark place into sunlight...or a small-ish solar cell that sends a ping to a server.   

       Also some pulls the bullet from the case, the bullet gets exposed to light etc...   

       Or an obelisk on the moon...sorry, wrong annotation..
not_morrison_rm, Jan 10 2014
  

       No need to mess around with photosensitive markings that might not function at night or in a darkened room; just use a chemical that reacts with the propellant gases. It'll work every time.   

       It occurs to me that if a substance could be engineered to gradually decay at a fixed rate once 'activated' by exposure to propellant gas (or the shock of discharge, maybe) then it wouldn't even have to be a legible stamp, just a small pellet embedded in the tail of the bullet. Determining the degree of decay would give forensic examiners an exact elapsed time since the bullet was fired.
Alterother, Jan 10 2014
  

       // exact elapsed time // sp. "approximate elapsed time". Other than radioactive decay (which is difficult to control the start time), most decay processes are sensitive to environmental conditions and the exact composition of the material. But that could be a fairly low-cost way to implement a time stamp.   

       Hey back to radioactive decay... If there was an element XX that underwent radioactive decay to become element YY, and YY was chemically reactive with lead or some other chemical that could be mixed into the bullet, but that chemical reaction would only take place at temperatures that would only be seen when the bullet was fired, then by comparing the concentration of ZZ, reacted YY and unreacted YY, the approximate time of manufacture and time of firing could be determined. Assuming all YY would react when the bullet is fired, the only innaccuracy would be based on how fast the bullet cooled (less than a minute?), as well as the accuracy of the instruments used to measure the concentrations.
scad mientist, Jan 10 2014
  

       a tiny amount of tritium in the very closest bit of propellant would work, add a small amount of material in the base which would capture the radioactive steam.   

       This would only tell you how old the cartridge was though.
bs0u0155, Jan 10 2014
  

       Wow, great discussion.   

       For clarification - in my mind, this was more for law abiding citizens than it was for criminals. Criminals will always find a way around legal limits.   

       But if you're a police officer or legal gun owner, knowing exactly when and where your shots went, in order, can be very helpful in piecing together what happened in a gun fight. And it seems to me that even if only half of the bullets used had this information, it would add credence to the chronology of an exchange of gunfire.
simpleknight, Jan 11 2014
  

       For law enforcement officers, it's simpler, cheaper, and much more useful evidentially to equip them with body cams.   

       For legitimate private users, the percentage of occasions where this would be useful doesn't justify the cost and complexity.   

       Criminals will simply disable or circumvent the system.
8th of 7, Jan 12 2014
  

       //And it seems to me that even if only half of the bullets used had this information, it would add credence to the chronology of an exchange of gunfire//   

       The knowledge that firing time and other information is hard-coded into bullets may be very beneficial to our hard-working law enforcement officials who occasionally have selective/jumbled/missing memories in court.   

       Actually, the Taser equipment does data log, which is useful, adding simple data logging to guns used by officials would be similarly useful.
bs0u0155, Jan 12 2014
  

       A tiny discharge sensor with corresponding time stamp could probably be built into existing (but rare) biometric palm sensor grips. Add some kind of simple GPS hardware (don't know how small that can be made) and you've got a gun that knows where, when, by whom, and how many times it was fired.   

       One high tech gun is much better than a box of high tech bullets.
Alterother, Jan 12 2014
  

       Note a few additional items:   

       There are many situations where body cams either aren't possible, likely, or effective:   

       Certain undercover ops and running and shooting come to mind.   

       Also, while adding this feature to a high-tech gun would be ideal, it would only make sense if that price of gun was standard. I'm not sure, but I think that a weapon like this would be less expensive than a palm locked gun, and I doubt bullets would be significantly more expensive depending on what material was added to the rounds. Putting numerical info on the back of the casing would seem to be a matter of laser etching or variable stamping, both technologies that already exist.   

       I do agree, though, that a smart weapon could (and arguably should) add this as a feature. However, if the bullets could be identified to the gun more easily and their shoot order somehow established, I would think that would still be a useful benefit.   

       I agree this might be of limited interest to a private citizen, although one imagines you could get an insurance reduction if you owned such a combination.
simpleknight, Jan 12 2014
  

       GPS can be made tiny now, they're in watches. The added benefit, of course, is that GPS provides a hyper-accurate external time reference, since GPS satellites are just orbital speaking clocks.   

       However, if you have 10 officers firing 10 guns, you may end up with 100 bullets in and around people/things, the gun information will tell you that they were fired at roughly the same time in roughly the same place. Some robust way of gaining more information from bullets would Shirley be useful? Especially if a gun gets "lost" or "accidentally destroyed". Equally, "secure" electronics are often found to be ludicrously easy to spoof/hack/clone a few years down the line (e.g. 50% of hotel door locks were found to be vulnerable to a simple hack).   

       I think you could make bullets using lead doped with traceable isotopes. Even mildly radioactive ones would be fine, bury radionuclides on the bullet interior. Or as suggested, microdots may also be incorporated. Both could be combined by manufacturers so that a bullet found could be traced> manufacture date, shipping date, shipping location.   

       The other "gun end" solution should just be stolen from WW2. Fighter pilots claimed to have shot down more planes than wrecks were found. So they put "gun cameras" on aircraft. Modern cameras are good enough and cheap enough that a gun could have hours of recording. Simply have it activated by the palm readery thingy.
bs0u0155, Jan 12 2014
  

       // although one imagines you could get an insurance reduction if you owned such a combination //   

       Unlikely in my estimation. Insurance companies distrust new tech and don't like anything that even resembles a gun, choosing to rely on social stigma and ignorance rather than credible statistics when calculating homeowner policies (i.e. the idea that ownership of more than one firearm increases the likelihood of accidental discharge).   

       My guns are insured as part of my policy, and I get a nominal discount because I own safes and strongboxes and trigger locks. Not all companies insure firearms, and not all that do offer these discounts. Some offer a discount for owning a safe but not for trigger locks. Some only offer a discount if the policy holder also owns a separate safe for their ammunition. I had to jump through a great many hoops to get my discount since I fabricated my gun safe myself (I defy anyone to break into it in less than an hour); finally an adjuster came to our home and examined it before signing off on my policy, and even then she tried to gig me for undeclared firearms when she spotted several non-functional .45s in the bottom drawer.   

       Given all this experience, I'd be surprised if the penny shavers would put any faith in firearms security measures more modern than a combination lock.
Alterother, Jan 12 2014
  

       Hmm. at least in my experience, the insurance industry is rarely swayed by stigma and opinion. They tend to rely on the costs generated by previous policies and the resultant claims.   

       Anything that increases the complexity of a claim, and crucially, the likelihood of it going to court, are going to have a strong effect on policy cost. They want 0 man hours, or as close as possible, on any claim, as the admin costs alone can quickly outstrip the size of any checks written.
bs0u0155, Jan 12 2014
  

       I agree with that assessment in general, and they certainly go to great detail in defining their criteria, but that seems to go all out the window when they discover you're a gun owner. So many people who live outside of 'gun culture' (I dislike the term) see 'gun' and think 'violence', and it seems to spill over here. In addition to the claim that more guns = more mishaps, they also seem to think that more guns = more break-ins. I can find no credible evidence to support these claims, but I've had it told straight to my face just the same. They don't go about it the same way as insuring a car or a boat or Heidi Klum's legs; the questions they ask about your firearms are inane, and the answers you give need to be very carefully considered. They won't even ensure my most valuable rifle, which I custom built myself, because the serial numbers on the barrel and lower receiver don't match.
Alterother, Jan 12 2014
  

       <Dredd>   

       "Double ... Whammy ... "   

       </Dredd>
8th of 7, Jan 12 2014
  

       //They don't go about it the same way as insuring a car or a boat or Heidi Klum's legs;//   

       That's because it is unlikely that one of Heidi Klum's legs will be stolen and used kill a clerk in a botched convenience-store robbery. Remember, they're gambling their money. They only have to screw up once to be liable for a whole lot of money. Which is why anything new and different makes them nervous, because they have no historical data to go on. Normal they like, millions of cars used for millions of hours, lots of data. Few surprises.
bs0u0155, Jan 12 2014
  

       These things that you say make excellent sense. Are you sure you're on the right forum?
Alterother, Jan 12 2014
  

       Let's build a space elevator out of Hemp!!!
bs0u0155, Jan 12 2014
  

       Just read an article (see nano RFID link) that shows a way to track particular substances to their source. Granted, this is designed for a small amount of tracking. But I imagine that combining a handful of different nano RFID tracers could lead to a system that would allow batches of bullets to be traced. At minimum, you could have police ammunition for each precinct have a tracer embedded. Of course then you'd have to make sure nobody got their hands on those.
simpleknight, Jun 09 2014
  


 

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