Posted on 01/11/2013 7:40:27 AM PST by marktwain
Major improvements have been made in 3D printed AR15 rifles. The part of the rifle that is defined as a gun by federal law is the only part printed. The rest of the parts are commonly available on the free market.
People have made guns at home since guns were invented in the 1500’s or before. However, the ability to print out your own AR15 lower receiver at home, without having to use steel files, a grinder, or other home workshop tools, has caught the attention of the public in this digital age.
Defense Distributed is the organization that aims to make the promise of the Second Amendment a practical reality for everyman at the touch of a button. No longer will criminals in and out of government be able to be reasonably certain that their victims are unarmed.
The first AR15 lower printed by Defense Distributed was matched to a barrel chambered for the 5.7x28 cartridge, a pistol/rifle round less powerful than the more common .223. It failed after six rounds.
All of their design work and testing is now being done for and with the .223 cartridge. Several different printers and technologies have been tested. Stress analysis with sophisticated engineering design tools has been used to reduce the number of prototypes required. The lowers will now work reliably for 40-60 shots before failing. The highest round count so far has been over 80.
The failures occur at the rear take down pins, through to the hand grip.
Defense Distributed believes that their latest improvement will be reliable for 100 rounds. They expect to release the build files to the public in the next few weeks.
They will dedicate it to Joe Biden and company.
Dean Weingarten
At the very least, greatly bolster the thickness of the web at the rear and upwards to the threaded area where the buffer tube attaches.
But I agree, a blank sheet design context might be in order. I have an old paperback edition of the Koran that I would donate as first prize.
Obviously its the material, the durometer of the material is too low. 3D printing should advance at a blistering pace, I predict the cost will come down of those that can handle more robust materials or the advent of a type of material that can be chemically or thermally cured.
I read somewhere that Daimler Bentz has a prototype metal printer that uses laser cutters. They say it will print almost any metal. I’m sure it will cost a fortune though.
The buffer tube is the weak link, especially as they have chosen the carbine configuration. I think they should dispense with the threaded buffer tube socket and make a solid rifle stock integral to the receiver. Increase the side wall depth a few millimeters and the bottom depth 2 centimeters to increase strength and use a rifle buffer spring and rifle buffer to reduce loading. The only thing I can't visualize is how you would engineer the selector detent.
How long before some lefty demands (and perhaps in some lefty jurisdictions, enacts) “3d Printer Control”?
I don’t object to such “control” in the narrow sense of saying “don’t make [things that are already illegal] with your 3D printer.” I’m talking, rather, about limits on having 3D printers AT ALL. It’s coming.
Yesterday someone on FR linked to an EBay listing of an “assault rock.” Satirical, of course, and very well written.
The Liberty One-Shot Pen might also make a great project.
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The 3/4” pipe and shotgun shell project doesn’t require a $5,000 3D printer.... can be created by anyone for about $2. I would like to see a single shot .22 or .25 pen though ,, stealth is VALUABLE.
EBay listing of an “assault rock.”
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Sharia Approved?
Wake me when they start printing M124s ...
Meant M134s ...
Heh, the comments actually got into that. He pointed out how this rock was superior in geological composition to the paltry “sandstone” rocks used inthe Intifada.
The lack of ammo is the Achille’s Heel of firearms. Tried to buy any lately? Those 3D printers will never safely replicate brass casings. Or primers. I shoot muzzleloaders and can cast lead balls and even make my own black powder, but I and most people don’t have access to the chemicals to manufacture primer compounds; that is dangerous as hell anyway. The best I can do is chip flints for my flintlock.
I would love to have a what appears to be a cell phone but has a working firing mechanics for at least a single shot .22lr.
Could be easy enough making a snap on printed extended battery pack with the guts in it, I have one for my Samsung Galaxy 2.
A friend was telling me this morning that Thursdays are now being called "Black Friday Thursdays" at our local Sportsman's Warehouse (Albuquirky). He was there yesterday afternoon, just checking things out.
The truck comes in Thursday morning. The store doesn't even open until around 9 AM, but reports are that folks are lining up a 3 AM just to get their hands on anything useful (mags, ammo, ARs - no guarantee they're even on the truck).
They were getting 1,000 round boxes of Federal .223 loose in the box, and apparently yesterday they sold all 50 boxes they received that morning ($406 each - including taxes) - they aren't even stocking the ammo on the shelves, just putting it out in shopping carts - it doesn't last long enough on the shelves to stock them.
Nothing of note left on the shelves, some obscure hunting rounds, but no .22LR, 9mm, .38, .45, 40S&W, .357, or .44 magnum, .30-30, .308 - gone. All semi-autos (rilfes/shotguns/handguns) sold out. Only firearms left were some bolt-actions, pump shotguns and a few revolvers. Even the reloading shelves are emptying out.
There is a thread on AR-15.com of someone making receivers from a $1600 makerbot printer. I think he beefed it up some at the typical failure points. The raw product looked rough, but was functional for more than 6 rounds.
There is a 3D print company in Sweden that uses electron beams instead of lasers, and can create items using titanium.
I think the bigger concern will be patent violations. Was the AR creation based on another company's design?
I think you are right on all accounts.
Rather than a patch at a point, the design/material needs to be tweaked/redone to reach durability without adding labor and specialized pieces.
That will come. Or possession of a 3D printer will be prima facie justification for a SWAT raid.
Give them a bit of time and perhaps the caseless ammo propellant can be 3D printed.
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