3D Printed AR15 Much Improved, More Reliable


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Dean Weingarten
January 11, 2013, 10:28 AM
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 1500ís 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

Pictures and working links at the site:

http://gunwatch.blogspot.com/2013/01/major-improvements-have-been-made-in-3d.html

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M-Cameron
January 11, 2013, 11:01 AM
wow, nice work!

have you looked into modifying the external dimensions of the lower to "beef" them up to better deal with the stresses?

Dean Weingarten
January 11, 2013, 11:10 AM
They are working it. They have considerable talent and some money supporting them now. It is happening. They sound very confident.

I believed that this interim report would be of interest, as the old media is ignoring them.

gunsandreligion
January 11, 2013, 11:15 AM
You really need to start on a 30rd mag that is easily printable. It would show the futility of a capacity ban.

Dean Weingarten
January 11, 2013, 11:22 AM
They are working to have printed standard capacity magazines. They say that the magazines are very easy to do. I posted a story on the files available for an AR 15 magazine, and Cody Wilson of Defense Distributed says that people have successfully printed AK magazines without a problem.

More later when I have enough for a story.

poboy6
January 11, 2013, 11:24 AM
I want to see video footage!

Silverado6x6
January 11, 2013, 11:29 AM
I have seen the 5 round printed AR mag, won't be too difficult to make larger ones.

With a 1.5 million back order of AR mags a person can get their money back pretty quick after buying a printer and making several dozen a day.

Doesn't matter to what degree any mag law takes effect, anyone can now make their own, the tech cat is out of the bag.

Dean Weingarten
January 11, 2013, 11:40 AM
The important thing for statists is that they are illegal. In a generation or two, grandpa's old AR15 and magazines will be turned in for an extra food ration.

What they aim to do is to eliminate the gun culture in America, and teach all to be serfs. They are well on their way. It is cultural Genocide.

Dean Weingarten
January 11, 2013, 11:41 AM
I think there is video footage at the Defense Distributed link.

gunsandreligion
January 11, 2013, 12:08 PM
Thats why grampa has to teach his grandkids to value that ar15. The key use that I see for these 3d printed weapon parts it the arguments they provide for the futility of a AWB. I believe the majority of politicians only veiw the topic of guns as an issue to get votes. Therefore the mindset of the people is so important, and having government controlled education is much more effective than gun control at suppresing the sheeple.

Kramer Krazy
January 11, 2013, 01:24 PM
I wonder how many rounds they'd get out of the lower if they built it into a 9mm version. :evil:

TheGloriousTachikoma
January 11, 2013, 02:32 PM
their blog also says they're testing 20 and 30 round printed magazines, too

Jim NE
January 11, 2013, 02:43 PM
Nice post, Dean.

Look at the Dept. Of Justice graph that tracks violent crime during the twentieth century, and there are two obvious high points:

1) Everything after the late 1960's

2) Prohibition (after organized crime got their act together)

And the black market for banned guns will be at least as great as the black market for alcohol. Welcome back, Al Capone.

HorseSoldier
January 11, 2013, 03:25 PM
You really need to start on a 30rd mag that is easily printable. It would show the futility of a capacity ban.

This.

Doesn't matter to what degree any mag law takes effect, anyone can now make their own, the tech cat is out of the bag.

And this.

The analogy to bath tub gin back under Prohibition seems apt.

gdcpony
January 11, 2013, 04:01 PM
I think I can work the reliability and lengthen the life of these after printing with a simple bracket. If that failure is what I believe it to be.

Claude Clay
January 11, 2013, 04:08 PM
in the mid 70's i worked at a tab house ( an appendage of Gallop Poll in NYC) and back than computers were huge and our color copier was a $40,000 machine. long story short--seems the go-for boys at the office were printing money using the copier. mostly 1's and 5's to buy park joints, gamble and pay for lunch. at least thats what they told the Treasury Men who tracked the money back to us about 9 months after we got the machine. so the T-Men 'adjusted' our machine and put a special lock on it ( free, go figure...) so that the green of money could not be produced. this copier was so good it even did the security color threads in the money.

if they can adjust one type of machine---id wager they can do it to others. so it may be that 3-d printers are going to have special default programs and/or be registered.

M-Cameron
January 11, 2013, 04:28 PM
if they can adjust one type of machine---id wager they can do it to others. so it may be that 3-d printers are going to have special default programs and/or be registered.

they really cant register 3d printers......as it is currently possible to print a 3d printer with another 3d printer.....

also, money is pretty easy to "lock out" as it all looks the same.......what does a gun look like?

gunsandreligion
January 11, 2013, 04:39 PM
If they put software blocks on, it would only be a matter of time before there was a "jailbreak".

M-Cameron
January 11, 2013, 04:42 PM
If they put software blocks on, it would only be a matter of time before there was a "jailbreak".



well the thing is, 90% of the software out there is open source....its not coming from a company, you really cant mandate a software block on opensource software.

even if they could, how would the software work?.....like i said, what does a gun look like?......

there is no way to differentiate a 'gun' from a 'bracket'....and assuming they somehow could, you simply change the model cosmetically enought to get around the software.

wacki
January 11, 2013, 04:47 PM
this it's excellent talking points to be used against those anti gunners that only worry about crime.....

Sent from my SCH-I500 using Tapatalk 2

joeschmoe
January 11, 2013, 04:51 PM
The printers needed cost $15,000 -$25,000.

That just gives you a stripped lower and in line behind everyone else trying to buy parts for their stripped lowers.

Barrels and springs cannot be made this way.

M-Cameron
January 11, 2013, 04:56 PM
The printers needed cost $15,000 -$25,000.

That just gives you a stripped lower and in line behind everyone else trying to buy parts for their stripped lowers.

not true.

there are many printers available for <$1,000.

if you want to build it yourself, they can be had for ~$400.

Skribs
January 11, 2013, 05:04 PM
I wonder, with this technology, if we'll see custom options as being more readily available? If they can put in different specifications and create products, then they can probably have more variants of the same model (i.e. right-hand, left-hand, etc).

There would be no sure way to structure the software so it couldn't be used to reproduce a firearm. So essentially, this makes the idea of even if congress could wave a magic wand to make every gun that isn't in a US military or police armory disappear mean that guns will still exist. Criminals can print them. If criminals can print them, I want to be able to have them, too.

Dean Weingarten
January 11, 2013, 05:11 PM
The printers needed cost $15,000 -$25,000.

That just gives you a stripped lower and in line behind everyone else trying to buy parts for their stripped lowers.

Barrels and springs cannot be made this way.
They are coming. I predict that barrels and springs for a printable firearms shooting standard ammunition will be available on printers costing less than $10,000 current value dollars in 10 years. They might need a little easily availabe heat treating.

They are coming.

I believe it would take little for a cnc machine to turn out hundreds of pistol barrels a day now. Those machines are available for about $20,000 today.

Kramer Krazy
January 11, 2013, 09:17 PM
I would love to get ahold of one of their damaged lowers and glue it back together for a desktop paperweight/conversation piece.

nwilliams
January 11, 2013, 10:30 PM
Funny I was just thinking the other day. There is local gun buy-back going on this weekend and they are giving $200 per "assault rifle". So I wonder what would happen if you printed off 100 AR lowers and took them to a buy-back:D

joeschmoe
January 11, 2013, 11:06 PM
not true.

there are many printers available for <$1,000.

if you want to build it yourself, they can be had for ~$400.
Those printers won't work for printing guns. They could make something that LOOKS like a gun, but it won't work. It can't be done on the budget printers.
To use the better materials and tolerances you need the $15,000 printers.
They guys who are doing this are not using cheap printers.

M-Cameron
January 11, 2013, 11:16 PM
Those printers won't work for printing guns. They could make something that LOOKS like a gun, but it won't work. It can't be done on the budget printers.
To use the better materials and tolerances you need the $15,000 printers.
They guys who are doing this are not using cheap printers

i beg to differ.

i have a fair amount of experience with 3d printing.

on a well tuned RepRap printer, we have been able to make functional tool holders for metal lathes.....if itll survive on a lathe, itll survive on a firearm.

we have printed springs that are damn near unbreakable.....trust me, weve tried.

when it comes to materials, they are most likely using ABS or PLA.....the industry 'standard'.....both of which are also used on hobby grade printers.

as for tolerances, here are the specs for the RepRap:
0.080” min. feature size, 0.004" positioning accuracy, layer thickness 0.012”

more than plenty accurate to print a lower.


i have no doubt these guys are using top-end printers, a top-end printer will likely print faster, and more consistent......but there is no reason it cant be done on a $600 printer.

Dean Weingarten
January 11, 2013, 11:48 PM
Are printed springs for a 30 rd magazine, or a 20, feasible in your opinion? It sounds like it.

mgmorden
January 11, 2013, 11:50 PM
Those printers won't work for printing guns. They could make something that LOOKS like a gun, but it won't work. It can't be done on the budget printers.
To use the better materials and tolerances you need the $15,000 printers.
They guys who are doing this are not using cheap printers.

Might not work for a receiver - but I'd be willing to absolutely bet it'd work for a magazine.

During the last AWB when production of mags was illegal you could still buy hi-cap springs to service your existing mags, and the followers are the same between 10 rounder and hi-caps, but are typically also made of plastic and could be printed too.

The fact that the hottest selling magazines for an AR15 are already polymer is just further proof that we've essentially hit a technological point where banning magazines will be pointless. Anybody who wants one for any non-lawful use could print one up quite easily.

If you look at Anonymous, Wikileaks, and The Pirate Bay, you can already tell that the government as a whole is mostly throwing it hands up in frustration regarding the taming of the digital age. They simply can't restrict the flow of bytes and what computers can do.

M-Cameron
January 11, 2013, 11:55 PM
Are printed springs for a 30 rd magazine, or a 20, feasible in your opinion? It sounds like it.


i dont see any reason why you physically couldnt print a 30 round spring....

that being said, it wont likely be in a realistic form factor. the most successful printed spring ive seen have been 'serpentine springs' with a thickness of ~1/8 THK. they take up A LOT of space when compressed.

so youll likely end up with a 30 round mag that will be the length of a 60 round mag.....and i cant imagine it being too terribly reliable.

MartinS
January 12, 2013, 09:44 AM
We'll need new designs, printable designs. They'll look some weird. The boys and girls who cling to their blued steel and walnut beauties will have more heartburn to add to their Glockburn. Hope we can have them all.

zoom6zoom
January 12, 2013, 10:32 AM
Most recent episode of CSI:NY they showed some giuy printing a revolver. Fully functional, moving parts and all, no assembly required. Part of me laughed at it, but the general public won't understand that current state of the art is not even withing rock throwing distance of that capability.

Silverado6x6
January 12, 2013, 10:50 AM
http://defcad.org/wp-content/uploads/2012/12/AR-15_Magazine.jpg

http://www.freerepublic.com/focus/bloggers/2976274/posts?page=41

I can order an affordable 3D printer right now from Amazon and can be making mags immediately, the one shown here is a 5 round AR type. The code is open source, the mag works.

Should not be too difficult to make one for the M1A. I would actually prefer 10 rounders to a larger mag.

Trent
January 12, 2013, 11:34 AM
They need to fore-go the conventional buttstock.

They need to build the lower with an integral buttstock in thumbhole configuration, capable of accepting the recoil tube as an insert instead of attaching the buttstock as a threaded attachment.

At that point the weakest link is eliminated.

barnbwt
January 12, 2013, 12:27 PM
Those printers won't work for printing guns. They could make something that LOOKS like a gun, but it won't work. It can't be done on the budget printers.
To use the better materials and tolerances you need the $15,000 printers.
They guys who are doing this are not using cheap printers.
Check out FormLabs Form 1 stereolithography printer. I've been touting them lately, since I think they are going to deliver a great product once it hits market, and they fit nicely between the Repraps and 15K$ industrial machines with a ~3K$ printer. Volume is 6x6x5" I think, and uses a liquid polymer solidified with a laser to build parts. Accuracy is around 10micron, I believe (I may be missing a decimal :o) and strength/finish is on par with injection molded acrylic plastic (material strength varies with polymer, of course). The goo is a little over 100$ for 1L, which is pricey compared to ABS, but not compared to machining the thing ;)

Most recent episode of CSI:NY they showed some giuy printing a revolver. Fully functional, moving parts and all, no assembly required. Part of me laughed at it, but the general public won't understand that current state of the art is not even withing rock throwing distance of that capability.
Don't you bet on it. Aside from the need to reinforce a couple things (barrel, chamber tubes and firing pin) a low-grade revolver capable of firing a couple low-power shots is likely possible at present. Granted, it'd go out of time or wear out the sear in a couple shots, but it would be about as durable as the el cheapo Spanish/Belgian knockoffs of American revolvers at the turn of the century. But yeah, a guy simply printing a S&W 27 from CAD models off the internet would only accomplish the murder of his hands and eyes :D

Printing assemblies is already being done:
http://cdn.shopify.com/s/files/1/0183/2285/files/Gyro_large.gif?2
From FormLabs website (http://formlabs.com/products/our-printer)
(PS, cool that we can link gifs here-didnt' know about that :))

TCB

RockyMtnTactical
January 12, 2013, 01:32 PM
that is awesome, and I would guess that they will get better and better with time. Excited to see the progress.

HorseSoldier
January 12, 2013, 08:49 PM
so youll likely end up with a 30 round mag that will be the length of a 60 round mag.....and i cant imagine it being too terribly reliable.

If they limit legal mags to 10 rounds, a 20 rounder the size of a 30 round mag wouldn't be a bad deal.

And, as was noted up thread, if replacement springs and followers are still available for existing mags, being able to print a 30 round magazine body is all you need.

dcarch
January 12, 2013, 10:28 PM
Wait a second... what about using the 3d printers to make magazines for firearms that are older/harder to find? Seems like it would be whole lot easier to "retool" a 3d printer than a machine shop.

BHP FAN
January 12, 2013, 10:37 PM
I like your 9mm idea better.

TheGloriousTachikoma
January 12, 2013, 11:45 PM
@ dcarch, the problem is that with an AR-15 the stack is significantly narrower than the magwell. Aluminum and steel mags have ridges that keep things in alignment and polymer mags simply absorb the space. The issue with pistol mags is that the stack is as wide as the magwell. All you have is thin-gauge steel. I doubt printed polymer would be strong enough.

But damn good idea.

also, reading through the blog post on the 30-round magazine, I see a couple of problems:

1: The feed lips need some fine tuning

2: The printed body and follower do not have sufficient lubricity against each other to move freely. The inside of a polymer magazine is glass smooth and the followers are usually IM delrin plastic. We need either a self-lubricating printing fluid or these magazines will require some post-printing finishing.

Silverado6x6
January 13, 2013, 03:54 AM
The 3D printer may make its mark in history as the machine that will manufacture the next generation Liberty pistol.
A one or two shot derringer style, will actually and safely shoot low pressure rounds. Possibly with a novel approach of an integral suppressor. A completely disposable weapon that leaves no rifling marks and no consistent firing pin mark.

That CSI episode I think was more about creating a negative image of making gun parts with a 3D printer, the giveaway is of course its in NYC.

I would love to see a new TV series about modern day gunsmiths creating parts and alternative weapons with the 3D printer. Even a new style of caseless ammunition?

sonick808
January 13, 2013, 04:09 AM
This is excellent news. Can i use a self-made reprap or does it have to be a makerbot

Diamondback6
January 13, 2013, 04:28 AM
Sonick, the guys at DefDist are specifically designing for RepRap and against MakerBot, as the MakerBot site has declared its hostility to guns and home 'smiths by deleting all gun-parts from their file-hosting site.

sonick808
January 13, 2013, 06:51 AM
good grief! All this on top of the recent announcement that the new makerbot is going to be closed source!!! Seems to me they've completely done a 180 from EVERYTHING they stood for.

how long until the government shoves their face into 3d printing ?

Trent
January 13, 2013, 11:57 AM
how long until the government shoves their face into 3d printing ?

It won't ever matter when or if they do.

No one has ever been able to stop piracy of any digital goods, ever, period.

barnbwt
January 13, 2013, 04:15 PM
MakerBot site has declared its hostility to guns and home 'smiths by deleting all gun-parts from their file-hosting site.


Cool, that makes my decision easier. I had been torn between the new Makerbot printer and the soon-to-release Formlabs SL printer. All these tech co's are probably gun-hostile, simply due to the backgrounds/demographics of the people involved (ivy-league egg-heads who've never been around guns), but if they aren't openly opposed to the legal use of their products where firearms are concerned, I say we should endorse them. I'll have to write them a letter before I confirm my preorder to see if they have a stance on this issue, or if they take a more libertarian mindset to how others use their printer.

TCB

Trent
January 13, 2013, 05:46 PM
Hey now.

I'm an "egg head", computer programmer, network admin, wide area communications work, database administration, high-availability server services. I'm actually a long hair hippy type wearing a tie died shirt at the moment. I like espresso, fine wine, filet mignon, fine art, classical music, and a good book in a warm tub. I study philosophy, and history, with an emphasis on "the condition of man" - what causes men to commit acts of evil, what causes empires to fall, what causes wars.

I also collect and own over 75 evil assault weapons... and know how to use them very well. :D

Can't judge a book by it's cover man!

MachIVshooter
January 13, 2013, 09:19 PM
2: The printed body and follower do not have sufficient lubricity against each other to move freely. The inside of a polymer magazine is glass smooth and the followers are usually IM delrin plastic. We need either a self-lubricating printing fluid or these magazines will require some post-printing finishing.

My thought is that it would be best to print the mag body as two halves and either use mechanical fasteners or fuse the halves after smoothing the inside.

Personally, I'll continue to do all my manufacturing on my lathe, mill, metal break, etc. Don't need a 3D printer to make a lower, and mine will not self destruct after 80 rounds, nor after 80,000. Neat as the 3D printing stuff is, the limitations of the material leave the products lacking in utility. Sometimes there's just no substitute for metalworking tools & skills.

Sambo82
January 13, 2013, 11:14 PM
There are now 3d printable mags. I'm very excited to try all this out once I can afford my own printer.

http://www.youtube.com/watch?v=q10Jz2qIog8

HorseSoldier
January 14, 2013, 03:07 AM
I'm an "egg head", computer programmer, network admin, wide area communications work, database administration, high-availability server services.

If anyone is familiar with Mil-Spec Monkey, that guy started out as a computer programmer for a video game studio (and may still be doing that as his primary gig in addition to his line of morale patches and military gear). We should be careful not to dismiss entire demographic categories as against the 2A based on stereotypes.

lumanaughty
January 14, 2013, 03:41 AM
Working for a large Internet company we have both pro-gun and anti-gun discussions on our internal mailing lists at times.

One of bosses at the company took the entire group clay shooting one time for a "team building exercise". There is a mixture of people, but I would say most from Silicon Valley are not pro-gun. However, there's many that are.

BHP FAN
January 14, 2013, 03:45 AM
so, wouldn't it be easier to build one in .22LR that would last? you could design them to take mags from the Colt/Umarex .22 M4.

barnbwt
January 15, 2013, 10:34 PM
I posted this email in a similar 3D SLA thread in Rifles; I'm gonna send it to Formlabs and see if they have an opinion on this "conundrum"

I am strongly considering putting in a pre-order for a Form 1 printer. I am impressed by the strength, quality, and economy of your product's capabilities, and it appears to be well-received by all who have written about it. I am somewhat dismayed by the decision to develop the Form 1 around proprietary software and polymer material, but I understand the need to protect patents and trade secrets by doing so. Hopefully, once your enterprise achieves success and financial stability in the marketplace, Formlabs will consider allowing open development so users may improve upon its innovations.

Before I make my decision to patronize Formlabs, I had a few questions I hope can be easily addressed:

-Is the vendor that manufactures the proprietary polymer recommended for use in the Form 1 large enough to satisfy demand should the platform become popular quickly?
-Are the Form 1 units themselves (or the polymer) being manufactured in the United States? Is the software being developed domestically?
-Do the laser-emitters or other components in the Form 1 have a known life-expectancy (as do the fusers in FDM machines)?
-Does Formlabs have an opinion regarding their products' use for printing legally-manufactured components for firearms?

Thank you for answering my questions. I am very impressed by the product Formlabs is offering, and I hope to do business with you all shortly.

Hopefully I'll hear back from them at some point and I will relate their opinion for all to consider :). Lemme know if you think I should ask anything else!

TCB

tekno
January 15, 2013, 11:12 PM
ok Im a little confused - if you had the file couldn't you just use a CnC mill to make the parts.

I went over to the CnCzone and found This thread (http://www.cnczone.com/forums/hobby_discussion/24763-milling_ar15_lower.html) that may help

M-Cameron
January 15, 2013, 11:24 PM
ok Im a little confused - if you had the file couldn't you just use a CnC mill to make the parts.


if you have a 3D part file, and the right software...then yes, it is pretty simple to CNC the parts.....assuming you know how to properly use the Software, how to set up a Mill and tool table, and how to fixture the parts properly, and assuming you have the $15,000 for a CNC machine.


with a 3D printer.....you 'skin' the part with some software, and hit print.....

barnbwt
January 15, 2013, 11:26 PM
^Sure could, it'd just be a lot more expensive and more difficult to get right. Programming toolpaths that do a good job creating the shape you want at the quality you want is more difficult than you'd think, seeing as it's automated.

The beauty of Rapid Prototyping is that the software figures out what it needs to do to create the form you want, so your job basically ends once you have a solid model file available. Perhaps in a few years CNC/CAD will have progressed to this level, but not yet (so I still have a job ;))

If I wasn't so sure it'd be a pain to learn to program for, I'd consider buying one of the <2000$ CNC setups you see on Ebay now and then (that's right Ebay, I'd use your own service against your anti-gun agenda :evil:)

TCB

Diamondback6
January 16, 2013, 08:54 PM
barnbwt, best not to press--for now, take their silence as some degree of tacit approval. Why rock the boat when they haven't said anything one way or the other?

Lucifer_Sam
January 16, 2013, 09:29 PM
This:

I wonder how many rounds they'd get out of the lower if they built it into a 9mm version. :evil:

or this:

so, wouldn't it be easier to build one in .22LR that would last? you could design them to take mags from the Colt/Umarex .22 M4.

plus this:

They need to fore-go the conventional buttstock.

They need to build the lower with an integral buttstock in thumbhole configuration, capable of accepting the recoil tube as an insert instead of attaching the buttstock as a threaded attachment.

At that point the weakest link is eliminated.

And I'd bet you could get something that would last a really long time.

Since it cracked through the rear takedown pin you might be able to thicken that area of the receiver externally for reinforcement and put a longer pin in. Thats what I would be looking at doing, at least. Longer takedown pins shouldn't be too hard to fabricate.

TheGloriousTachikoma
January 16, 2013, 09:35 PM
The problem is work size. Integrating the buttstock increases the length quite a bit and most 3D printers that are marketed for 'home/hobby' use don't have much more work area than a lower or a magazine.

About the only way to do it would be to build a RepRap and double the X-axis. But then the software would need to be changed...

But something else that could be done is the integration of a spare mag holder, like the Kel-Tec SU-16A/B/CA or the new stock from Mako.

barnbwt
January 16, 2013, 10:05 PM
Larger RP forms are frequently made as interlocking pieces that are then glued together with epoxy that is stronger than the RP material itself. A little bit of finish work, but not much. These forms are also sometimes strengthed by "varnishing" with the same epoxy, or even by laminating fibers onto them.

At present, DD seems to be trying to copy existing designs, see where they fail, and adjusting accordingly. Iterative, but it will eventually work. They'll probably end up with a fairly durable lower/upper/stock strategically reinforced with simple sheetmetal parts (high wear, high stress areas). Hard to ask for more, really; an AR15 as easy to home build as a tube gun?:cool:

TCB

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