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Brady & Calif hearings on microstamping
Brady Campaign rejoices that a proposal for gun microstamping (putting tiny engravings on the firing pin to mark cartridges fired from the gun) has been shown to function.
Of course, the real issue is how little effort is required to defeat the measure. With a .45 and a spare firing pin, I'd say about 2-3 minutes. If they microstamp the bolt face, then it'd take a spare slide and about 45 seconds. And if you can't get the spare parts, I suspect a 15 second pass with a Dremel mototool would do the job.
[UPDATE: Refugee notes in comments that a legislator says they had a guy remove 70 microns from the firing pin tip and the marking were still visible. I've hunted around to get an idea of whether 70 microns is significant enough to where removing more would cause a malfunction. It doesn't look that way. This webpage on the Steyr Scout says factory tolerances for firing pin protrusion are ".050" - .059" (1.3 mm – 1.5 mm)." This military manual indicates that for an M-1 tolerances are broader: "The minimum should be 0.044 inch and the maximum should be 0.0590 inch." And here's an exchange about the Remington 700, saying tolerances are .055-.060," and he used .052" but had some misfires.
I haven't found the specs for handguns, but these would indicate that the tolerances in question are at least about .2 mm, and at most over 1mm (.05"). Since a micron is a thousandth of a millimeter, seventy of them would be .07 mm. This suggests that the amount removed in the test is far less than factory tolerances would allow, let alone how far it can be taken before the gun malfunctions. You might be able to take 3-10x that much off without going out of tolerance]
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I actually emailed Ladd Everett with the word, "sandpaper", and he emailed me back: "Dave, read Assemblyman Koretz's attached release. He went at the pin with diamond paper, took 70 microns off the tip of the firing pin, and the microstamped markers were still visible. There's a redundancy in the technology that no common "thug" (as you so elegantly put it) is going to be able to defeat, and experience tells us that the overwhelming majority won't even try..."
The press release said, "It was essential that we had an unbiased witness present who had the technical expertise to analyze whether the microstamping characters were still legible on the cartridge shell which was fired after the firing pin had been filed down. Also, we needed to use a weapon that was equipped with microstamping rather than La Suer’s own weapon.
La Suer’s absence did not deter Koretz from doing his own testing of the microstamping technology. Using several types of household files, he was unable to file off the characters. Although he was able to remove about 70 microns from the tip of the firing pin after applying a special diamond paper; expert examination with a microscope by John Rush, a Firearms and Impression Program Manager for California Criminalistics Institute, of several cartridges fired from the weapon after this filing, showed that the microstamped characters were still visible, because of the redundant feature of the microstamping system."
Now, this sounds bogus to me. Seventy microns isn't that much, and I have a hard time believing that a few swipes with 320-grit silicon carbide paper, or, indeed, a touch or two with a Dremel tool, isn't going to take off enough to obliterate the markings while still leaving the gun functional.
But I lack the technical expertise to confirm details. By how much can you shorten the average firing pin and still "bust a cap"? What about other chamber and barrel marks?
(Of course, there are other objections, like the fact that the gun is likely to be stolen, and that this is really just a registration scheme that will burden the law abiding far more than the criminal. But I'd like to nail down the details before responding.)
70 microns is a small fraction of a millimeter.
Look at the depth of the impression upon a primer and tell me that taking away even a full half a millimeter would stop the gun from firing. And I dont even think this would be necessary. You can merely sharpen the pin to a point to remove markings from around the edge without removing its ability to indent the primer. Or buy a spare one from out of state, etc.
If you put the markings on the bolt face, you could easily remove remove them without hindering the ability of the firearm to seat the cartridge or eject it. Most combat firearms have gaps in the bolt-face anyway to allow a frame protrusion to smack the cartridge free. You could remove plenty of material from the average bolt face without affecting functionality in the slightest.
When lathes and milling machines are outlawed...
This microstamping tech is pretty pointless on a revolver. Unless of course revolvers are outlawed.
What's to stop a criminal fron picking up some of your microstamped brass off the range then leaving a couple at the scene of the crime!???
What's to stop a criminal fron picking up some of your microstamped brass off the range then leaving a couple at the scene of the crime!???
There will be a law against doing that.
Law enforcement will be exempt.
Of course they'll make removing the firing pin or bolt engravings prima facie evidence of a crime, just as removing the serial number is now. But we know the goblins go to great lengths to obey that law, don't we?