Intro:Given the ubiquity of semiautomatic designs based on the AK-47 in the USA's civilian market (and the ubiquity of the real thing in so many other places), I thought there should be some FAQ entry. Please accept the following submission for the FAQ file, outlining the history, function, and versions of "AK-47" type guns.
Disclaimer:This document is provided as-is, for public distribution, without any guarantees of accuracy or correctness. The author disclaims particularly any liability for events that may occur from acting upon the information contained herein. The names of particular models imported into the USA are trademarks of the respective corporations. This does not express the opinion of my employer.
Note: information presented here is gathered from personal experience, manuals of guns I have owned, and Edward Ezell's book, "The AK-47 Story".
History: This family of weapons originated with a design by Mikhail Timofeyvich Kalashnikov, a soldier of the Red Army, during the Second World War. Kalashnikov took up small arms design while recovering from wounds sustained in a tank battle. His goal was to design a cheaply manufactured, automatic weapon that fired the new Soviet 7.62x39mm intermediate power round. This round was intended to be a compromise between the pistols rounds fired from submachine gun, which were controllable but lacked power, and the rifle cartridges fired from heavier machine guns, which were either too heavy to fire while on the move or, if lightened, uncontrollable during automatic fire. The conventional wisdom is that the Nazi's originated the concept of an assault rifle with their MP44 machine-pistol design, (which fired the 7.92x33 "8mm Kurz" round) and the Soviets copied them, but this is disputed by Ezell -- both sides may have developed such weapons concurrently. Furthermore, Kalashnikov was hardly the only _Soviet_ designer working toward this end at this time. Other designers looking at the 7.62x39 cartridge included Simonov (designer of the SKS) and Tokarev (designer of the weapons that bear his name). Kalashnikov's weapon was designed from the outset to be:
Theory of Operation
I will only describe semi-automatic fire. For a discussion of full-auto AK-47's see Edward Ezell's book.
The safety lever serves two functions when in the upper or "safe" position. First, it blocks dirt from entering the action by covering the slot the bolt carrier lever moves through when the weapon is fired. This also prevents the weapon from being cocked while on "safe". Second, an extension on the pin holding the lever through the receiver blocks the rear of the trigger, preventing the trigger from being pulled. When the safety lever is moved to "fire, the action may be cycled, and the trigger is the only thing holding the hammer from falling. When the trigger is pulled, the hammer falls, hits the rear of the firing pin, and the round detonates. Note that the AK-47 bolt is locked closed by rotating when the bolt carrier is moved forward (there is a cam on the top of the bolt that engages a slot in the bolt carrier to accomplish the rotation). The firing pin is free-floating -- there is no spring to hold it retracted until the hammer falls. Consequently, if one manually cycles live rounds through the AK-47, one will observe light indentations on the primers where the firing pit hit against them as the action closed. Consequently, it is inadvisable to chamber live rounds unless you are prepared for the possibility of the weapon firing when you do so. Slam-fires do not seem to be as common as with the SKS (According to military personnel who have posted to rec.guns, it is hard to get enough dirt into the action to cause it to malfunction for that reason. I recall one report of flawless functioning even when the rifle was so covered in mud as to be hardly recognizable as a firearm.)
The action is gas-operated: when a round detonates, some gas from the explosion is vented out of a small hole at the top of the barrel near the muzzle. This gas pushes against the front of the piston in the gas tube, which is connected to the bolt carrier. As the bolt carrier is pushed rearward by the gas, the bolt rotates to unlock and moves rearward, and the round in the chamber is extracted and pulled back. The round is ejected when it hits against a small portrusion on the left side of the reciever as the bolt moves rearward. Simultaneously, the back of the bolt pushes the hammer back and cocks it. The hammer is held back by the disconnector (the trigger is almost certainly still pulled, since the action cycles much faster than the operator can release the trigger). The bolt and bolt carrier recoil against the recoil spring and guide rod, and come back forward. As the bolt comes forward, it grabs the top round from the magazine and puts it in the chamber. There is no feature to hold the bolt open after the last round is fired from the magazine. When the operator releases the trigger, the disconnector moves rearward and releases the hammer to move about 1/8", at which point it is stopped by the (now released) trigger until the operator pulls the trigger a second time.
Notes:
1. Tolerances are very loose. The pieces of this rifle need not fit together perfectly in order for it to function, or even to be reasonably accurate (I would like to see how the AK variants currently advertised in the USA as "National Match" pieces do :-) ). Expect it to rattle around a bit. If you don't like that, get something else instead.
2. The use of stranded springs is supposed to add reliablility against breakage -- the idea is that a single broken strand does not disable the weapon.
Takedown and Cleaning
1. Remove the magazine and set it aside.
2. Move the safety lever to "fire"
3. Pull back the bolt carrier lever and eject any round from the chamber.
4. While holding back bolt carrier lever, visually inspect the chamber to
make sure it is empty.
5. Push the bolt carrier forward.
6. Press in the button on the rear of the reciever cover.
7. lift the rear of the receiver cover, disengage the front of the
receiver cover from the slot in the rear sight housing. Pull the
reciever cover free and set it aside.
8. Notice that the button you pressed in step 6 is the rear of a rod
with a long spring around it that goes into the rear of the bolt
carrier. Push the rear of that rod forward until it disengages from the
rear of the receiver.
9. Lift the rod up and backward to remove it and its spring from the bolt
carrier. Set the rod aside.
10.Push the bolt carrier lever to the rear and lift the bolt carrier upward
to remove it and the bolt from the receiver.
11.Remove the bolt from the bolt carrier by moving the bolt foward and rotating
it until comes free from the bolt carrier. Set the bolt and
bolt carrier aside.
12.With a punch or your hand, rotate the lever on the right side of the r
ear sight upward about 90 degrees.
13.Remove the gas tube and handguard by lifting the the rear of the tube
and disengaging the front of the tube from the barrel attachment it slides
into. Set the gas tube aside.
If you desire to disassemble the bolt (easy) or trigger group (hard), you're on your own.
As they say, "Assembly is the reversal of dissasembly."
You should be able to disassemble and re-assemble this rifle blindfolded in under 1 minute.
Russian Military Versions
AK-47 1st 2nd 3rd models, AKM, AK-74, Dragunov SVD
The Russians apparently couldn't decide whether the stamped metal receiver was a good idea or not. The main differences in the AK-47 models 1, 2, and 3, and AKM (the M stands for "modern") have to do with the construction method and rear sight. The AK-74 uses the same operating principles, and looks similar, but fires the 5.45x39 round, and was adopted (not surprisingly) in 1974. The Dragunov SVD is a sniper rifle firing the 7.62x54R cartridge, but functioning in the same manner as other Kalashnikov system rifles.
Other Military Versions
Chinese type 56
Galil .223
Valmet (Finnish)
Hungarian
Yugoslavian .308
Self-Loading Versions Available for Civilian Purchase in USA
All rifles imported after the 1989 semi-auto import ban are sold with 5-round magazines, no bayonet lug (and consequently no way to attach the cleaning rod to the rifle), and thumbhole stocks. There are some rifles floating around imported prior to that date. Expect to pay a hefty premium for one of them.
Egyptian Maadi: supposedly made using surplussed Russian tooling, and thus most similar of all AK-variants to the original Russian AK-47. The stock is generally a "laminate".
Mak-90, NHM-90: Semiauto copy of Chinese model 56. 16.5" barrel, chromed bore, stamped receiver and trigger. Receiver appears to be blued, bolt carrier and bolt appear to be chromed (like Chinese SKS bolt carriers and bolts).
NHM-91. Also Chinese-made. Longer, heavier barrel. Higher quality stock. Some receivers are milled from cast metal rather than stamped, but not all of them.
SA-93: Bulgarian. Cast receiver and trigger. 16.5" barrel. Chromed bore. Hardwood stock painted brown. Bolt carrier, receiver, cover, and barrel finished in some sort of black enamel.
Yugolsav: As mentioned above, some versions fire the 7.62x51 NATO (.308 NATO) round. Longer barrel than MAK-90.
Hungarian: no information other than its availability as of October 1996 through ads in the Shotgun News.