AKs may have a reputation for being simply built and easy-to-use firearms, but for those who are not intimately familiar with them, they can be the source of a lot of confusion, which leads to a lot of questions. What’s an AKM? Are AK parts interchangeable? The list goes on, and before we get into it, let’s recognize that no firearm has ever been produced in greater numbers — more than 100 million and counting — or by as many different nations, more than 30, including the U.S. AKs come in many different flavors, and although we use “AK-47” as a catch-all term, early-era AK-47s are not the most common of the variety.

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In the U.S., the AR has been the king of tactical rifles for a long time, but it is increasingly facing stiff competition from the growing number of AK aficionados. The AK remains the most popular and well-recognized rifle in the world, and for good reason. The design is simple and robust. It can be mass-produced quickly and at low cost. Its ergonomics may be lacking, but the simplicity of its controls and method of operation makes it very easy to quickly train troops to use. It is compact, lightweight, powerful and incredibly reliable, even in the worst conditions. News photos of combat zones routinely show AKs with broken or missing stocks, missing dust covers, taped-together parts, coated in rust and filth, and yet they are still functional.

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In the U.S., aftermarket manufacturers are also joining the fray with a huge host of new accessories that improve and address the AK’s few deficiencies. To understand more about the world’s most populous long gun, we will sift through and answer some frequently asked questions about the AK platform.

1. What’s the main difference between an AK-47 and AKM? Are most rifles we see on the market now actually AKMs?

Kalashnikov’s original AK-47 design called for a stamped-steel receiver, where a flat piece of metal is stamped, cut, folded and welded to manufacture the receiver. The advantages to a stamped receiver include cheaper, easier and faster manufacturing. However, due to production issues, the design was altered to use a milled receiver instead. Here, a solid block of steel is machined to form the receiver. This resolved the problems with the manufacturing of the receiver, but also increased production time, cost and overall weight.

Eventually production problems with the stamped-receiver AKs were resolved, and the AK-47 became the AKM. The “M” stands for Modernized, while the “AK” stands for “Avtomat Kalashnikov”, which is Russian for Kalashnikov’s automatic rifle. The AKM was first adopted for use in 1959 and largely replaced the AK-47 in the Soviet Union and its satellite states. The overall dimensions remained the same. The dust cover on the AKM is thinner and lighter than on the AK-47, so designers added ribs to increase rigidity.

2. What are the major parts of an AK?

See the diagram in the gallery above.

3 . What is the difference between milled and stamped receivers? Is one type preferred over the other?

Milled-receiver AKs are easy to identify, mostly by the rectangular lightening cuts on either side of the receiver that are meant to reduce weight. Some folks view the milled-receiver guns as superior because of their heavier and stronger construction, as well as the greater attention to detail in the milling process. Conversely, stamped-receiver AKs are lighter, cheaper and quicker to produce. In practice, there are no functional differences between these receivers.

4. Why do some receivers have dimples in them while others do not?

The dimples on stamped AKM receivers just above the mag well are meant to help stabilize the magazine. Milled AKs don’t have them because the receiver is thick enough to do this on its own. Thanks to some senseless legal reasoning (is there any other kind?), some imported stamped AK receivers were required to be fitted for thinner single-stack magazines, making the dimples unnecessary (and thus removed). When these receivers were retrofitted to use standard staggered magazines, metal was added inside the receiver at the mag well instead of dimples to serve the same function. Some people prefer dimples for cosmetic reasons (it makes it look like a true AKM), but it really makes no difference functionality-wise.

5. Can furniture be swapped between stamped and milled receivers?

Handguards and pistol grips can often be swapped between stamped- and milled-receiver AKs, but most buttstocks cannot. If you want to replace the buttstock on your AK, make sure to buy one that is specific to your gun. Also, some handguards may not fit on different AKs, especially some Yugoslav-made models and other non-100-percent standardized models, regardless of whether they are stamped or milled. Always check with the manufacturer in advance.

6. What differentiates the AK-74 from the AK-47 and AKM?

The main difference here is the caliber. The AK-74 uses the lighter and faster 5.45×39mm instead of the 7.62×39mm.

The Russians were looking to copy the results of our own M16’s 5.56x45mm round and decided that a lighter, faster bullet is more accurate, allows the soldier to carry more ammunition and produces better wound ballistics. The new cartridge has a less tapered profile, and AK-74 magazines have less of a pronounced curve than AK-47 magazines. Other differences are that the AK-74 introduced a new muzzle brake to reduce recoil (which has also been adapted to some 7.62x39mm AK variants) and it has a gas block with a 90-degree angle instead of the 45-degree angle of the AK-47. The sharper angle prevents bullet shearing with the newer, faster ammunition.

7. Is the AK modular like the AR-15? Are parts easily interchangeable between AKs?

If you have two AKs made by the same factory, using Russian specifications, you should have complete parts interchangeability. Many of the countries that make AKs do so under contract with access to Russian specs. But also, many others do not and may have reverse-engineered their AKs. Because of this, most parts should be interchangeable — but not always, as it depends on the source of the parts.

8. What are the optic-mounting options on an AK platform rifle?

Originally, there was no easy way to mount an optic on an AK. Eventually the Russians and others added an optic base on the left side of the receiver. A dogleg mount allows you to attach a scope at the rear of the rifle above the receiver cover. A mount is not simply installed on top of the receiver cover because this is not a stable platform and your scope will not hold its zero. Some manufacturers have fixed this problem with much sturdier receiver mounts that actually attach at the rear sight (by replacing it) and at the rear receiver extension (where it attaches to the buttstock). Another option is to replace the rear sight or the top handguard with one that includes a Picatinny rail. This allows for the use of a forward red-dot or holographic optic or a magnified optic with unlimited eye relief.

9. What is the purpose of the lever over the gas tube on some AKs?

This rifle is most likely a Yugoslav (now Serbian) AK. That lever above the gas tube does two things. First, it is a gas cut-off device that prevents the rifle from cycling. Second, it is a grenade-launcher sight. Using a blank AK round and a muzzle adapter, Yugoslav AKs were designed to also fire rifle grenades.

10. Why do some AKs have two slots in their handguards and some have three?

Those slots are there to help vent and cool the rifle barrel during firing. Two is the standard, but in some countries the handguards are longer (the former Yugoslavia and Iraq being two examples). In practice, it makes no difference.

11. It seems as if all slings made for AKs are two-point. Are there other AK sling options?

Most AKs have two sling attachment points. Depending on where the AK was made, these may be located at the sides or at the bottom or some mix thereof. There are adapters that place the sling attachment point at the front of the buttstock or the rear of the pistol grip, and these will work well with single-point slings. Any sling will work with an AK for the most part, and you are not limited to two-point slings, although most people prefer them.

12. What does 922r-compliant mean?

In 1989, President George H.W. Bush signed a ban on the importing of military-style rifles. While U.S.-made military-looking rifles were not affected, ones not made in the U.S. were banned. As a result, AKs (and other foreign firearms) that you find in the U.S. after 1989 either feature “thumbhole” stocks and non threaded muzzles or are retrofitted to be “Made in the U.S.” thanks to Title 18 Chapter 44 Section 922r of the United States Code, referred to as “922r” for short. The 922r  rule defines what is a “U.S.-made imported rifle” by limiting how many foreign-made parts are in said rifle. Of the 20 imported parts listed in 922r, not more than 10 of them can be in a compliant rifle.

For it to be lawfully compliant, the rest of the firearm’s parts must be made in the U.S., and they are usually so marked. This matters, because if you buy an AK and want to install original foreign-made parts (to give your rifle a more authentic look or to save money), you will need to be mindful of the AK’s overall imported parts content. If you’re not careful, you may be in violation of the law if you assemble your rifle with more than 10 imported parts. Off-the-shelf AKs made by reputable U.S. manufacturers, importers and sellers should be 922r-compliant. When in doubt, confirm with the manufacturer.

13. When looking at AKs, there seems to be emphasis regarding the country of origin. What do I need to know about this?

Different countries have different standards of quality and consistency in their AK manufacturing processes. Some manufacture AKs under license from the Ruskies, and some do not, taking liberties with the design as well. All of these rifles work in the same fashion in terms of functionality, and the real differences are in what steps are taken to return the rifle to its military look. The rest is just preference and cosmetics for collectors.

14. There seem to be a lot of designations among AK platform firearms from Saiga, VEPR, Dragunov, Krinkov, Maadi, etc. What are the major AK-pattern rifles?

The basic AK design was used for everything by the Eastern Bloc countries. Why reinvent the wheel? Need a squad automatic machine gun? Start with an AK. Need a special operation submachine gun? Start with an AK.

Briefly, a Saiga is made at the only factory to ever make real AKs in Russia. A VEPR is made at the MOLOT factory from RPK (squad automatic weapon) receivers, which do not have 100-percent parts interchangeability with Saigas and are built sturdier. The Dragunov is the Russian sniper rifle chambered in the archaic but still effective 7.62x54R cartridge. It uses a different gas system than the AK and therefore is not considered to be one. The Romanians make their own version called the PSL that looks similar to a Dragunov but uses a real AK gas system. The “Krinkov” is an unofficial nickname for the AKS-74U, which is the folding-stocked, short-barreled AK for vehicle crews and spec-ops forces. The Maadi is the name for the Egyptian-made AK.

15. Some Saiga rifles don’t look like traditional AKs. Why is this? Are they easily convertible from rifle stock to pistol-grip configuration?

To comply with our import laws, the Russians have to alter their Saigas to bring them into the U.S. (of course, now we have a total import ban on Saigas because of the whole Crimea business). Once in the U.S. and with the requisite number of U.S.-made parts per 922r, you can convert it back into a normal-looking AK. If you do this, make sure to find a quality builder, as it is not a simple process.

16. What do I need to look for when buying an AK?

Since most AKs available in the U.S. have been rebuilt using a mix of U.S. and foreign parts, and since you may not be familiar with who rebuilt it or their reputation, it is always best to do a thorough function check on any AK. Check the alignment of the front and rear sights, check the safety lever to see if it overshoots its position either up or down, check the function of the trigger and its reset. There are also a few manufacturers making all U.S.-made AKs with no foreign parts. We would recommend these function checks on any AK regardless.

17. Can a canted front sight be easily fixed?

By you or us? No. But a gunsmith with the proper tools and knowledge? Yes.

18. It is said that AKs are ultra-reliable even when not cleaned. How long can I go without cleaning an AK for it still to perform reliably?

Until it stops working. You will likely start to experience issues with ejection and possibly cycling at some point, but that may be at the hundreds or thousands of rounds mark.

A lot of this depends on conditions like weather and ammunition.

19. Do AKs come in chamberings other than 7.62x39mm and 5.45x39mm?

Just 7.62x39mm and 5.45x39mm for “real” AKs, although some countries like Poland that have joined NATO now produce their AKs in 5.56x45mm. The Israeli Galil, which is an AK variant, was always chambered in 5.56mm NATO, and there are also U.S. conversions of AKs in .223 Remington. You can buy AK shotguns that fire .410, 20 and 12 gauge, and there are Saiga and VEPR variants chambered in 7.62mm NATO/.308 as well as 7.62x54R.

20. Are there American-made AKs?

A few companies are making 100-percent made-in-the-U.S. AKs. This includes Century Arms and Inter Ordnance, Inc.

21. Is the Galil rifle considered an AK-platform rifle? How about Sig’s SG 550, Rock River’s LRA-47 and CMMG’s Mk47?

The Israeli Galil is a true AK variant, as is the Finnish Valmet. To a purist, a true AK must use a long-stroke gas-piston system of operation. The Swiss Sig SG 550 could also be considered an AK of sorts, although the design is very different. ARs and other AR hybrids that have been chambered and converted to accept AK magazines and fire 7.62x39mm are not AKs even if they have gas-piston operation.