Building your own firearm
    As surprising as it may seem to some, there is nothing illegal about building your own gun. Of course, a home built firearm is not exempt from the same local and federal laws which regulate commercially made firearms. In essence, this means that you can not build anything which you would be unable to buy. Things which could get the home builder into trouble are the manufacturing of fully automatic, or silenced firearms, pistols or semi auto rifles where they are banned, and the inclusion of things like flash hiders, and bayonet lugs, since these are not permitted on guns built after November of 1994. You can also not build certain models of semi auto rifles, using foreign made parts.
    Firearms manufacturers must be licensed, and pay a fee, if they are going to sell to the public. This does not mean that you can not sell any firearms that you make, without being licensed as a manufacturer, but does limit you in scope. The law is somewhat vague on this point, saying in effect that you can sell guns you make for yourself, but can not specifically make guns with an intent to sell. This rather large gray area leaves a fair amount of latitude for prosecutors, and judges, as well as for less than honorable citizens. Things like intent, malice of forethought, and premeditation are notoriously hard to prove or disprove. Of course, circumstances do play a part. If you are building, and selling, a dozen guns a month, it is pretty obvious that you are manufacturing with an intent to sell. on the other hand, two guns a year might a reasonable amount for someone who likes to tinker, but does not wish to have a house filled with firearms.
    The most popular pattern firearm to home build is the AR-15. There are a number of reasons for this, not the least of which is high availability of parts, from a number of manufacturers. Then there is the easy availability of drawings, manuals, and accessories, and finally the high cost of the factory made guns themselves. You actually can save some money by building your own, though not as much as some people claim. A home built gun, made from parts, from a manufacturer such as Olympic, DPMS, or Bushmaster, will probably cost about $600 to build. The same gun, from the factory will probably sell for $800 or so. Building a Colt is not really an option, since Colt receivers are not generally available to the public.
    Other suitable and popular candidates are the FN-FAL series, the Ingram series, various Kalishnikovs, along with the CTME and G-3 types. There is also the Colt 1911 pattern pistol. The reader has probably noticed that these are all military guns; this is no coincidence. Military small arms are the epitome of the mass produced firearm. They have to be. Civilian guns often require a certain amount of hand fitting, and certain sills and tools, nor ordinarily possessed by those with only a casual interest n firearms.
Parts guns
    The easiest route is to build a parts gun. I have actually built several, and the process is not really much more difficult than detail stripping for cleaning. In the case of most military small arms, the process is rather easy. Parts are acquired, manuals gathered, and space is set aside for assembly.

Building from a semi finished receiver

    For the prospective home builder who does not own a machine shop, a number of partially finished reciever/frame units are sold. These tend to be castings that are not machined to exact dimensions, and have not been tapped, drilled, or finished. They can be purchased in many different stages of completion, from 40% to 80% finished. These unfinished castings cost between half and a third of what the finished product would cost. For an AR-15 lower, you are talking (in 2002 dollars) 60 to 90 dollars for your basic alloy receiver of standard quality. Similar units, completely finished from Olympic, or DPMS will cost 120 to 200 dollars, in standard trim. Units built of bronze, stainless steel, sintered metal, or titanium are available at considerably more cost.
    I tried this once, and frankly have to admit that it is just too much trouble. The only advantage to it, over the production of a parts gun, is that this can give you an off the books firearm. The assumes a certain amount of criminal intent, since it is illegal to produce a firearm, and then not give it a serial number.
Scratch Building.
    Prison zip guns are an ample demonstration that it is possible for the average man to put together a firearm with the most meager materials and production facilities. It can be hoped, however, that anyone reading this wishes to produce something at least a bit above the level of a zip gun.