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Semi-Full Auto

    For those who don't wish to spend a big chunk of their lives in prison, there are ways to get a reasonable facsimile of full auto. There are basically two classes of device which will allow a semi auto to function as a full auto. The members of the first class are legal for unlicensed use by ordinary citizens, and take advantage of the BATF definition of what constitutes a full auto arm. The BATF definition of a full auto arm requires that more than one round be fired for each pull of the trigger. The legal devices will actually pull the trigger for you. They may be in the form of a crank or of a spring loaded device which uses the motion of the gun during recoil to pull the trigger as rapidly as the gun can cycle and fire. There is also a class of full auto devices which mimic the action of a true auto sear, but require no modification of the gun. These devices are class 3 devices, as they work upon the mechanism of the gun itself rather than the trigger. Examples of this class of rapid fire device are the lightning link, and the drop in auto sear. These devices are covered under the National Firearms Act of 1934, as are machine guns, short barreled rifles, silencers and some other classes of weapon. All of these devices are commonly referred to as NFA weapons; Auto weapons are officially referred to as class 3 weapons.

Class 3 Devices
    A class 3 device is considered to be a machine gun by the B.A.T.F. and must be registered to be legal. Registration requires finger printing and a photograph, a $200 transfer fee, a background check, and a wait (as long as several months). The form must also be signed by either a judge, or by the head of a local law enforcement agency. If approved, this form will get you a stamp which must be affixed to a registration form provided by your friendly local class 3 dealer. These devices must have a unique serial number, and are themselves considered to be firearms. One last hurdle is the requirement that civilian users are only permitted devices manufactured (and registered) before 1986. Non-compliance with any of these requirements makes the mere possession of these items a felony, and a Federal crime, punishable by up to ten years in prison and a $10,000 fine. Interestingly, these penalties are far more severe than those given to rapists, bank robbers, muggers, and even murderers. These devices require no permanent modification of the firearm, as would be required for the installation of a factory auto sear.

This is the link for the AK-47, and AKS series of rifles. The curved ends catch notches at the end of the AK hammer, and hold it back until the link is tripped by the forward movement of the bolt. It is shown approximately twice actual size, and may be easily inserted, and removed from the weapon. The picture was taken from an add on an Internet web sight where it was being sold; don't ask me for the address. As there is no serial number on the piece, and the seller in question is not a class 3 dealer, I can only assume that the device in question is illegal, and being sold illegally. As may be seen, this is simply a flat piece of spring steel which has been cut and bent to size. It can be produced easily with minimal equipment for a couple of dollars, and yet I see these bits of prison bait selling for hundreds of dollars.

This is an example of the so called "Drop in Auto Sear" for the AR-15 rifle, as in the case of the preceding example, this is shown approximately twice it's actual size. This device is a bit more difficult to fabricate than the above device for the AK. The drop in sear actually requires some machining and milling be done; it is also composed of two parts, one of which is a moving part. These too are selling for much more than their complexity, quality, and cost of manufacture would mandate. In all of these cases the cost is a reflection of the non-compliant, black market nature of these devices. I want to emphasize that it is not illegal to own these devices, but legal ownership is highly regulated, and expensive. Like the above device, this requires no modification to the firearm. The upper receiver of the AR-15 is tipped up, and this device is placed at the rear of the action with the toggle placed towards the front. The pin holding the rear of the upper receiver also holds the drop in sear in place. After installation, the toggle performs the function of the auto sear, by being forced down when the bolt returns to battery. when the toggle is forced down, it presses upon the disconnector, causing it to release the hammer. As long as the trigger is held back the rifle will continue to fire. This device has no effect on the primary sear, so the rifle will stop firing when the trigger is released.

This is a "lightning Link" the cheapest and most infamous of all of the auto sear devices, being cut or stamped out of a flat piece of sheet metal. The lightning link has earned itself quite a reputation in certain circles, and caused quite a stir when it was first concocted. This is the "Saturday Night Special" of the full auto world, and as such, is the horror of the anti gun left. The Lightning Link functions in a similar manner to the drop in sear listed above, but depends upon the tension and rigidity of the spring steel used in it's construction to hold it in place, rather than being held rigidly in place by a block of steel. It is installed by clipping the two pieces together into a sort of an L shape. The longer of the two pieces goes around the trigger group, while the shorter piece sticks up behind the rear pin holding the upper and lower receivers together. As can be seen in the photo, the lightning link goes over the disconnector, and is held in place be a tension between the disconnector and the rear pin holding the receivers together. When the bolt  comes all the way forward, it increases the tension on the link which in turn puts tension on the disconnector, pulling it off of the hammer sear and releasing the hammer. The lightning link need not even be bought, as it is so simple to make that any one with a Moto-tool, or even a pair of tin snips could fabricate one. This is a pretty good illustration of the main pitfall of these types of devices, and the danger they can present for the user. This is so easily and cheaply made that it may not be taken very seriously by the experimenter, or the curious until they find themselves staring at a long prison term and hefty fine.

    Besides the obvious legal problems, there are some other problems with the drop in sears. First, though the drop-ins mimic the action of the factory sears, these are not true auto sears, and can be some what temperamental. It must be remembered that the firearms in which these devices are used, were not originally designed to produce full auto fire in this fashion. Proper adjustment and reliability can be a matter of luck. Since many of these devices are produced in backyard, and basement shops, they are not something I would want to stake my life on, or put into a firearm which I may someday have to rely upon. The other problem with these devices is that the rifle is transformed to fire in full auto mode only. The only way to convert back to semi auto is to open the action and remove the drop in sear. In the real world, semi auto fire is far more useful than full auto in all but a few situations.
    On the plus side, these devices are cheap if you make them yourself, they do work, and they leave no permanent incriminating modifications on your gun. Of course, you must decide if the potential legal problems are worth whatever advantage you think full auto capability will provide. I have some really mixed feelings about people having and using these devices. On the one hand I do not believe that the government has the right to restrict devices of this type, or machine guns, silencers, or any of the other banned weapons. These types of legislation would seem to be clearly forbidden by the Second Amendment. On the other hand, these laws have been made, and it is a not acceptable to have each individual making up his own mind about whether or not he ought to be obligated to obey this or that law based upon his own idea of the validity of the law in question. A better solution for the civilian, who is not anxious to flout the laws of the Federal government, might be one of the non NFA trigger devices.

Non-NFA Devices
   These tend to be crank, ratchet, or spring devices which work on the trigger rather than the hammer or disconnector. Since the trigger is pulled for each round discharged, these devices are not covered by the NFA of 1934, and federal restrictions do not apply to them. However, many local and state governments have seen fit to take it upon themselves to restrict the use and ownership of these devices. Though legal in most places, most of these rapid fire mechanisms are almost as over priced as the NFA type devices mentioned above. The best of them seems to be the Hellfire Device or later Hellstorm, which will work with just about any semi auto rifle. Many of the others do not work well with certain weapons. The Hellfire device puts tension on the trigger so that it is unstable enough to be set off by the inertia of the gun as it is fired. Similar designs are the tac trigger systems. I have actually seen master pistol shots do the same thing to semi auto pistols, using the index finger of their weak hands. Unfortunately, this is not an option for semi auto rifles.  The G.A.T. is a cranking device which is less touchy, but more cumbersome than the spring devices. If you are viewing this page at  600x800, the two photos on the left are of the hellstorm. The top photo is a close up of the device itself; the lower one shows how it is attached to an AR-15. Lower down, and to the right is a photo of the G.A.T. cranking device. Both of these photos were acquired at . I have no misgivings about giving out this address, as both of these devices are legal in most states, and may be purchased from the listed website. Certainly all of these devices violate the spirit if not the letter of the NFA, but as I consider the NFA to be an unconstitutional, and badly thought out set of restrictions, I don't lose too much sleep over it. I have not seen the old Tri-Burst device in ages, and must assume that the company has gone out of business. This device was a lever attached to the trigger guard, which when fully depressed would cycle the trigger three times in quick succession.
    One advantage that all of these trigger devices have over the drop in sears is that they allow the user to quickly switch over to single shot firing by simply bypassing them and squeezing the trigger directly. There is also the undeniable advantage of not having to find a hiding place for these devices, and of being able to use them without taking a chance on going to prison. Most of them can be had for between $30-$50, which is really quite a sum of money for a bit of wire, and plastic, but it does beat having to mutilate your firearm, and maybe being mutilated yourself by the legal system. Full auto fire can be a lot of fun, but it's practical uses are so limited that it is hardly worth the effort, and certainly not worth the risk. The civilian marksman and sport shooter will probably find his taste for full auto shooting more than satisfied by the legal trigger devices available.