UC Davis releases Mircostamping study

From NSSF, here is a copy of the full study on Micro-stamping as released by UC Davis.  Pay very special attention to this:

At the present time, therefore, because its forensic potential has yet to be fully assessed, a mandate for the implementation of this technology in all new semiautomatic handguns sold in the state of California is counter-indicated.

As I read over the full study, I keep seeing references which indicate the group pushing for micro-stamping because they control the technology is deliberately misleading people with their agenda.  One of the key things they talk about is how “easy” and “cost-effective” it would be to implement this technology at a manufacturing level.  The study from UC Davis would contravene that statement:

The vendor was supplied with 14 firing pins which were subsequently engraved at a cost of $3,500 or ~ $250.00 per firing pin.

$250.00 per firing pin?  That additional cost, even if it ends up being less, is going to either kill manufacturers or be passed directly on to you and I as the final consumers of the product.

Here are a couple of key excerpts from the study document on how easy it would be to remove the “micro-stamp” marks from the firing pin:

Two different methods were designed to evaluate the ease with which lasermachined micro-characters could be intentionally defaced or obliterated. In the first method, the firing pin for an AMT “Backup” 380 Auto semi-automatic pistol was held perpendicular to a household sharpening stone and rubbed back and forth for 30 seconds. The second method involved placing the firing pin for a Sig Sauer P229 semi-automatic pistol on its side on an anvil and rolling it back and forth while lightly peening it with a ball peen hammer for 15 seconds. The firing pin was then stood on its base and the tip was peened for an additional 15 seconds.

Finally, both defacement/obliteration methods demonstrated that the microcharacters could easily be intentionally destroyed with the firing pin removed from the firearm.

“Easily intentionally destroyed”.  Here’s another quote from the study regarding the ability of the markings to be easily read after repeated firings in a rimfire firearm:

Given the nature of this rimfire firing pin and firearm design, it was determined that a maximum of five out of the eight alphanumeric characters can contact the rim of the cartridge case, thus providing a maximum possible transfer rate of 63%. Over the 250 rounds of ammunition test fired, the average transfer rate of legible alphanumeric characters was 16%.

Essentially, this technology doesn’t work for rimfire firearms, and would add a significant amount of cost to the production of said firearms.

I want to go back and focus on is how easy it is to remove/deface the encoding information on the firing pins.  You hear micro-stamping advocates say “Oh, criminals won’t be able to get the firing pins out of these guns, it’s too complicated and takes tools”.  Table 4 in the study shows how long and what tools it took the researchers to get the firing pins out of the guns.  The longest time listed to remove the pin is 3 minutes, and the most complicated tools required are a punch, a hammer, and a bench block.

The best part is that once the test firing pins were out, the researchers were able to completely destroy the markings on the firing pin, re-install the pin, and still fire the gun – however none of the markings then transfered over.  For example, the Sig Sauer that they tested took 3 minutes to remove the pin, 30 seconds to destroy the markings, and 3 minutes to put it back in.  That’s 6 minutes and 30 seconds to make a complete end run around the new law.  Criminals may be dumb, but I’m pretty sure they can figure that out.

This is an actual peer-reviewed document, not some press release piece thrown out there.  While they did find that some types of laser engraving can transfer to cartridges, no single method transferred 100% of the encoded information to 100% of the cases 100% of the time.  Most hovered around the 60% range of data transfered, and several methods had much lower averages than that.  Couple that with the fact that all the encoding methods can be easily obfuscated in 6 minutes and 30 seconds (or less), it’s no wonder that the researcher’s final report says that there is no mandate for this technology.


  1. Keep in mind that once places like NY pass microstamping laws, they MUST pass bans on all REVOLVERS.

    As easy as it is to defeat the microstamping, it is easuer for a criminal to just get and use a revolver. It is hard to imagine any crime for which this weapon substitution would have any effect.

    Teh progession is: microstamping law; restricted selection of pistols (not all [any?] manufacturers will switch); revolver bans.

    Criminals still won’t care, but citizens won’t have any choices for their defense.

  2. I think you could remove the slide, push the firing pin forward of the breachface, mask with a little tape, and zap the end with a sandblaster.

  3. In the study, they did remove the pins to mess them up – for the guns they pulled the pins on they said it would be “difficult” to do with the pin still installed. Also bear in mind that 3 minutes to remove the pin was the longest it took – some took as few as 30 seconds to remove the pin.

  4. I’m guessing someone will figure out that you can just glue a tiny bit of sandpaper to the “primer” on a snap-cap, load it, and repeatedly fire it for 10 minutes or so. Anyone can sit around and come up with new ways to destroy the engraved tip of a firing pin. If that were the only difficulty with a law requiring this technology…

  5. No, I agree, Americans and criminals are nothing if not innovative. I think it’s important to get this kind of message out there that the technology is unworkable. If your state has legislation on the table that proposes using this kind of tech, send a copy of the study to your legislators.

  6. If one did manage to mess up a firing pin, how hard would it be to mill or grind out a new one? They’re basically just…PINS

  7. Or some enterprising thug with the few needed tools could set up a firing-pin scrubbing business for the less-mechanically-inclined criminals…

  8. B. Smith, note that there are currently no laws restricting the transfer of firing pins or other gun parts (besides the frame or reciever of a gun)

    So if a Crook lives in California or NY, they can just drive to Connecticut or Oregon/Nevada/New Mexico/Arizona ect and just BUY a bunch, if somehow their state makes it difficult to simply mail-order the part.

    It would be exactly like how hi-cap mag sales work here in Mass. They’re illigal here unless they’re pre-ban manufacture. Most mail order companies have been threatened with lawsuits from our AG so Mail-order here is a PITA and some companies won’t do ANY buisness with us.

    Still a 20 min drive to New Hampshire I could fill my truck to the brim with hi-caps and nobody will ask any questions. Its prefectly legal to do. We don’t do it because its a crime to drive across the state line with the mags in tow….and by “We” I mean people who follow the law.

    So unless these dumb laws get passed nation wide the only people who will have stamped guns will be lawful people…and REALLY dumb criminals.

  9. I’m far from any kind of expert, but I have watched a whole season’s worth of the cop show THE FIRST 48, which follows the first 48 hours of a real-life homicide investigation in a selected major American city.

    In NONE of the cases were the shell casings decisive to cracking the case. The were helpful clues, yes, to determining the caliber of weapon used. But in cases where bullets are recovered from victims, it’s the rifling characteristics compared to the murder weapon (if found) that was decisive, not the presence or absence of shell casings at the crime scene. Cops already know if you arrive at a shooting crime scene and there are no shell casings lying about, it’s a good working assumption that a revolver was used, or else the criminals had enough time to pick up their brass before fleeing the scene. Other clues that could be lifted from casings (like fingerprints) would be on them with or without “microstamping”.

    What is always key are eyewitnesses and people who can disconfirm an accused perp’s supposed alibi, as well as the best forensic evidence that can be gleaned from the crime scene. The investigators look for means, motive, opportunity.
    “Microstamping” is a red herring and a kludgy, hi-tech “fix” in search of a problem. Tried and true police work gets the job done without it, and wouldn’t be substantially aided by it, for all the reasons everyone has already discussed here.

    Making all guns prohibitively expensive by over-regulation seems like 2A infringement to me.

  10. I’m sure what’s not covered in the study is that microstamping, in a best case scenario, only takes you to the last “legal” owner of the firearm. Pretty much the same as if you recover the actual firearm itself & run its serial number. How often does that solve a case? I suspect not very often, except on TV shows.

Comments are closed.

%d bloggers like this: