You don't need to assemble all the parts, just the receiver since that is what is legally considered the firearm. Parts kits (minus receivers) are plentiful, cheap, and unregulated. Your local and state laws may vary, but it is generally legal to make your own receiver without any sort of license or taxation, provided it is for personal use. I would consider another make of firearm though; AR-15 type rifles have been successfully constructed with carbon fiber, polymer, and composite receivers. I've never heard of anyone doing that with AK series weapons, and considering the stress the AK receiver is under during recoil (find a slow motion video, it's jiggling everywhere!) I wouldn't really want to.

Mandatory I Am Not A Lawyer Statement

Manufacturing a firearm with a 3D printer would be a federal crime in the USA. That's not why I asked.

I'm more interested in actual costs of the democratization of force for places that don't already have weapons (unlike the USA).

Stop assuming that this.country == "US" when you talk to people on the internet, please.

Not a federal crime for some values of "manufacturing":

http://www.atf.gov/firearms/faq/firearms-technology.html#com...

"Individuals manufacturing sporting-type firearms for their own use need not hold Federal Firearms Licenses (FFLs)." So you could manufacture an AK receiver but you would have to outfit with a Saiga parts set to avoid falling afoul of 922(r) restrictions on "assault weapons".

I was only speaking to the U.S. as that is the only system I begin to understand the legalities of (and that would remotely allow this). The reality of an insurgency using 3D-printing to manufacture whole firearms isn't possible yet due to the stresses involved. I've had multiple mechanical failures due to MIM parts (metal injection molding) shattering in handguns. I can't imagine the current or near future 3D printing materials being able to surpass MIM in strength.

It would be more likely to be used to make difficult to manufacture components for weapons, such as molds for shaped charges.

Would aluminium do? Could you use the 3D printer to make a mould and cast some alu from drinks cans?

If you redesigned some parts to be all metal, you could probably (maybe) be able to construct it completely out of titanium.

Since Selective Laser Sintering (SLS) titanium has nearly the same properties of cast titanium, you could buy a printer in the sub 50k range.

You can legally own an AK, it just can't be fully automatic.

If you go with your assumption (US jurisdiction), it can indeed be fully automatic with the correct tax stamp.

Manufacturing a firearm with a 3D printer would be a federal crime in the USA. That's not why I asked.

I'm more interested in actual costs of the democratization of force for places that don't already have weapons (unlike the USA).

Interesting - as a private citizen, I was under the impression that I could not own a fully-auto assault rifle. I'd be interested in hearing sources that point to the contrary.

Great point about the democratization of force. I wonder if it's any easier than obtaining them on the black market in those countries.

With a 3d printer, it becomes not "those countries" but "every country, simultaneously".

PS: "fully-auto assault rifle" is redundant.

Actually, it only has to be semi-automatic to be considered an assault rifle.