Interesting article for the gun fans among us…
Holy Bifurcations Batman! As a police officer I was trained as an evidence techician and processed crime scenes for almost 8 years. I must have dusted thousands of items for fingerprints. This is HUGE! Fingerprint residue is comprised of water, fatty oils and amino acids. I wonder it if it is the oil or acid that cause the corrosion. It is huge because amino acids deposited on a piece of evidence last for years and years. We have had forty year old prints lifted using chemical preparations that tag amino acids.
It may have a problem though with “gang guns” - firearms that are used by multiple shooters. Does the ridge detail on later prints mask or obscure unlying prints (but are identifiable)?
Posted by sig94
01/02/2009 at 01:59 PM
If it’s acids in sweat doing the marking, everyone touching the case will leave evidence. It may be impossible to single out the last handler.
I foresee an uptick in the use of exam gloves among savvy criminals.
What are they going to do if gloved bad guys start picking up cartridges at police ranges to reload?
Posted by Chuck Kuecker
01/02/2009 at 03:25 PM
The operative expression is “savvy criminals.” And savvy criminals don’t use guns unless they absolutely have to and then they use revolvers for hits as no cartridges are left at the scene.
So we’re left with idiots. They’ll only use gloves if they look “bad” in them.
Something in sequins ala Michael Jackson perhaps?
Posted by sig94
01/02/2009 at 04:48 PM
I would hope the cops aren’t letting the thugs use their range Chuck. But you are correct in that you can get pick up brass just at just about any range. Of course, you’d have to have crooks who knew how to reload, and who purchased the right tools. We reloaders are still a fairly rare species, so the odds against my press being set up to make the right ammo for the thug’s gun when he breaks into my place and steals it are pretty slim.
Sig - will a bit of lye or something alkaline break down these amino acids?
I’d be mightily impressed if this micro-corrosion could stand up to case polishing, or even a quick dip in the old Iosso case cleaning solution.
This is a pretty cool post. Thanks Severa!
Just when I thought it was safe to supplement my income....
Drew- you would have to remove the layer of metal that carries the “imprint” so to speak. This could be done by acid but then you’d remove both the interior and exterior material. You’d have to be careful not to take too much off because you would run the risk of compromising the strength of the cartridge wall. Cartridges are designed to withstand a certain amount of pressure and then some overpressure depending on how the cartridge is commonly used. Probably some kind of mild abrasive like fine emery cloth would do the trick.
Posted by sig94
01/02/2009 at 07:31 PM
Oh, rats.
Um...does anyone know just how far back in the old homicide case files they’re looking?
...I was just wondering…
*shuffles off, nervously*
BTW: Drew - I wonder if a reloading press leaves a distinctive set of tooling marks, much like receiver backends, firing pins, barrel chamber, extractor, and rifling marks? You’d think the resizing die would, for sure.
Drew: I did a little reloading myself at one time, using a Dillon RL550B machine. What machine do you favor?
I’ve got a Dillon 550, myself. As far as tooling marks from the reloader, I don’t think you have much to work with unless you run without case lube. The only place you possibly would have tooling marks would be the neck of the shell, from the resizing die, and from the crimp die, if you use one. The Dillon does flare the case mouth at the powder station for pistol rounds, but those marks would probably get messed up when the bullet is seated and the load is fired.
Since most reloaders are careful to clean their brass before reloading, there would be little inside or outside of the case to act as an abrasive that would raise wear marks on the dies - and carbide dies are a whole lot harder than the shells anyway.
The idea of using markings in the chamber or on the bolt face was the original microstamping concept. Easily foxed with a Dremel tool and a touch of fine abrasive, once you find the location of the marking. Of course, they can eliminate this problem simply by making it illegal to polish gun parts, right? Passing laws has had such a great effect on crime so far!
The thing that scares me about registered guns where they require examples of fired cases be sent in with the registration is the fact that anyone could frame you by obtaining a few fired cases and ‘salting’ a crime scene with them.
I religiously police my brass, even my Berdan cases on my home range. Looks like it was a good habit to cultivate.
Posted by Chuck Kuecker
01/02/2009 at 09:46 PM
Whoo hoo, it’s a Dillon fan club! Yup, I’ve got the RL550B too, with almost all the options. I’m not wasting money on the power case feeder until they make it take rifle cases too. But mine has all the other goodies. I couldn’t count how many thousand rounds it has made; just give it a wipe and a couple drops of oil every once in a blue moon, and it’s good to go.
I even went with a couple aftermarket accessories from UniqueTek; everything but the micrometer powder bar. The toolhead clamp makes better ammo, period. It is straighter and has less length variation. The bearing race lets you tighten the shell plate a little bit more so there is less wobble. I think that helps too, but you wind up sorting your cases by rim thickness and making a tiny adjustment, so it doesn’t save you any time.
All my dies get a power polish on the inside anyway with some rubbing compound and then some Flitz. After cleaning dies come out mirror bright on the inside, they get a dose of TSI-301, and after that I can use less case lube. Almost none actually, or just get by with ISDW.
Sounds to me like you could get around the whole issue by using a shotgun. No rifling, plastic or paper “brass”. To be fair, it does mean you’d have to have the courage to get close to your target…
Or a baseball bat. Then set fire to the bat…
I load on a Dillon 650; everything from .32 ACP to .35 Whelen.
The technology sounds interesting. I’m of the mind the reloading process will distort any old prints on the surface of the case. It’s a pretty snug fit in that carbide sizer. Of course, any handling AFTER the loading process would be clean and new and show up well. Frankly, anyone I shoot will be a matter of public record, so I’m not very concerned over my prints being on the cases.
But I wonder if passing the ammo around among several people would sufficiently muddle the prints? Or would the last touch be readable?
This story is not over. When technology develops a measure, technology develops a counter measure. Same song, six thousand, four hundred and eighty-eighth verse.
My Reloader is the Dillon 1050.
Yes, It has case feed plates that handle .308 and 30-06.It may be true that prints can be lifted from cases.
That only proves that at some point that person handled the case,
Not that they are the shooter.Imagine a 30 caliber can full of bulk 9mm loads left open at a gun show.
How many people would come by and casually fondle the ammo?A really determined criminal might wear vinyl gloves and carefully bead blast all his loaded ammo for the Criminal endeavour.
The old school gangsters used electrical tape on their crime guns.
01/02/2009 at 07:58 PM
