It's not .22 revolvers that they're afraid of.
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Posted on 10/06/2012 7:46:27 PM PDT by marktwain
Printing Wealth, Not Dollars
Over the next few weeks Cody Wilson was going to make his own gun from scratch.
Developments in high-end design and manufacturing processes have brought the cost of doing this way down.
For a few thousand bucks, you or I can design and manufacture pretty much anything we want in our workshops, sheds, and garages.
The most important thing you need is called a 3D printer.
Once you have one, you can find designs on the Internet and print out almost anything you'd like.
Cody Wilson leased one. He planned to print out a pistol and share with others the know-how to do so. You know, because the right of the people to keep and bear arms shall not be infringed, and is necessary to the security of a free state.
But free no longer, you can imagine what your rulers and their enforcers thought about this idea. (Of course they knew about it: Civilian surveillance is up 64% under Obama after Bush opened up the rights-squashing gate with the (un)Patriot Act.)
Now, Cody is a second-year law student, so he's got a good grasp on his rights...
He knew he was well inside the law as long has he didn't try to sell his printed firearm. And it's certainly legal to share specs on how to do so.
(Excerpt) Read more at wealthdaily.com ...
I posted this in your other thread, but it all reminds me of the hysteria surrounding “plastic guns” when Glock first started importation into the US.
Media generated hysteria with an agenda.
Actually, I "just" read a report on 3D printing yesterday (in either R&D or Machine Design) , and the state-of-the-art has improved hugely. Laser-sintered metal powder 3D printing produces parts that are STRONGER than cast. I was kinda shocked, because I try to follow that area and had no idea of that advance in capability.
And not just any metal. High strength steel. Or a metal of equivalent strength.
NY requires a "valid pistol license" before one is "authorized" to own a hand gun, which must also be registered. Whenever anyone applies for a carry permit, they might not be "registering" their weapons, but they are certainly advertising to "authorities" that they have them.
Wow! That’s impressive. The company I worked at had one back in ‘98. It was pretty awesome stuff back then but it sure didn’t have all those materials available. Thanks for informing me. Things can certainly change in . . . Wow! has it been 14 years?! I am getting old fast!
Maybe printing these will end all the hate ....:o)
http://imageshack.us/photo/my-images/571/glock1911.jpg
Stay safe....
Well, the metal needed is driven by the chamber pressures.
Shotguns have relatively low pressures - say, oh, 14,000 PSI to 17,000 PSI. Black powder shotguns need even less.
Pistol/revolver rounds might reach up into the mid-30K to 40K region (for the biggest Linebaugh or Freedom Arms type rounds). 25 to 30K for most centerfire pistol rounds is a good number.
Rifle rounds can be anywhere from the mid-40K region up to over 60K PSI, “maximum average pressure,” aka “MAP” to firearms testers and proof houses. Near 70K PSI in a rifle, you start blowing out primers and case heads start to come loose.
OK, so what does this mean?
It means that many steels will actually suffice to hold in those pressures. The steel used in the receivers of the Springfield ‘03, Garand and M14/M1A aren’t what we currently consider especially high-strength steels. If you want a representative AISI number, go look at the specs for 8620, which was the steel of choice for the Garand and M14. The ‘03 was similar strength, different steel.
Barrel steels were “ordnance steel,” which spoke more of the quality than the yield strength. Today, most “chrome moly” steel barrels are 4140 steel, “gun barrel quality,” which is the highest quality of that particular alloy. Basically, you don’t want inclusions and pockets in the steel. Stainless barrels are typically made from 416 stainless - but mostly because 416 machines nicely, not because it is especially corrosion resistant or high strength.
4140 alloy is pretty common stuff. If I had to pick only one steel in a survival situation, I think 4140 would be high on my list of “good stuff to have.” You can harden it, you can work it annealed or quenched & tempered back, you get good machineability, good welding properties... there’s a reason why it is so popular in so many applications.
Springs: Springs are typically made from much higher carbon steel than anything else on a gun. Whereas the barrels are made from 4140 (which is 0.40% carbon), spring stock is typically 0.70 to 0.95% carbon - much higher. Typical spring AISI numbers are 1070 or 1095 - plain carbon steels with high carbon contents. This isn’t complicated steel to come by, but the heat treating of a spring is the issue here. You have to heat it to about 1450+ F, then quench in oil, then re-heat to about 650F to temper it. Putting it into a pot of molten lead works, or a bath of molten saltpeter works well too - and blues the spring at the same time.
None of these are especially “high strength” as modern material science looks at it. To see what I mean, compare the yield strength of 4340 steel to 4140, and you’ll see a modern “high strength” steel.
Pins and screws: Screws are machined out of “screw stock,” which is relatively weak steel that machines really nicely - like 1215 or 12L14. Pins will be harder stuff - the 1070 above would work, altho a tool steel might be a better option.
The point being: None of the steels in a modern firearm need to be what we call “high strength” - they’re good, don’t get me wrong. But that’s all they are: good. They’re not some wonder steel.
And... if push came to shove and you had to go back to black powder, you can make firearms out of malleable iron - not steel. The first gen Colt SAA’s, some of the Winchester rifles, etc were made of malleable iron - which is why color case hardening was so popular back then. It was the only way to keep the malleable iron from denting and scratching...
Looking at the alloys being used by the laser sintering and the print-n-bake printing outfits, it appears that they have the steels necessary for the action/receiver and barrel already in use in 3D metal printing. This doesn’t surprise me, because MIM gun parts are working just fine and are probably made from the same types of powdered steels.
I have no doubt that they’ll be able to make an entire gun on a 3D printer in the near future. It’s coming - as soon as some gun nut with the appropriate background gets near one of these half-megabuck machines for a weekend, it’ll get done.
Ever fill out a Form 4474?
Chances are, your guns have been registered in a DB somewhere where the LEOs have “conveniently forgotten” that it’s illegal for them to do so — also, I wouldn’t put it past them to track ammo & reloading-related purchases as well.
Thanks for the highly informative post. I don’t know much about metallurgy and it’s always nice to learn from an expert.
Based on your description, I don’t see any way, for instance, to make a usable spring with the printing technique. It might be the right shape, but would it be heat treated and tempered so as to function properly? Not as I understand the process.
They’re working on ways to make springs - they have different forms (much more complicated forms, in some instances - but they can do complexity easily in 3D printing), but they perform the same functions.
The problem in gun designs is that they’re very space-limited, and the current designs want either:
a) “flat” springs, such as you find inside a S&W revolver (eg, the mainspring), or in a side-by-side shotgun, or in older external hammer percussion cap rifles/shotguns. These are very easy for a trained gunsmith to make from flat spring stock.
b) “coil” springs, which gunsmiths make by winding music wire around a mandrel.
Both require high-carbon steel that has been hardened, then tempered.
The way they’re coming at it in 3D printing is to come up with complicated geometries that they can print, which, when put into a confinement tube or restricted in some volume way, turn lower hardness materials into suitable springs.
But even if you had to make springs, it’s easy. Really. Flat springs take some skill with a file and sometimes a hammer to forge them, but coil springs? Feh. Pud easy. Probably one of the easiest parts to make on a gun.
It's not .22 revolvers that they're afraid of.
<
Ever fill out a Form 4474?
Chances are, your guns have been registered in a DB somewhere where the LEOs have “conveniently forgotten” that it’s illegal for them to do so — also, I wouldn’t put it past them to track ammo & reloading-related purchases as well.
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My last gun purchase was in early 1980s. No forms to complete and no background checks here at that time.
Too bad about that canoeing accident.
This shows some 3D printing in impressive metals:
Additive Manufacturing using metals
http://3dprintingsystems.com/additive-manufacturing-using-metals/
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