3D Animation Showing How the AK-47 Mechanism Works

Matt Rittman, a 3D motion designer from Waukee, Iowa, has recently published a beautiful 3D animation demonstrating how the mechanism of a typical AK rifle works. Animations of the AK mechanism has been around for a while. Nevertheless, this one is rather well executed. Without further ado, let’s watch the video.

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Operating Systems 301: What Is Underlug?

Note: In this article, I call this mechanical feature “underlug”. However, this is an error. Several friends of mine and I have been discussing the mechanics of firearms operation for close to a decade now, and we misremembered the term “underslide” from a book by Brassey’s as “underlug”. More details on the error are available in the comments. Regardless, “underslide” is the proper term for this principle, not “underlug”.

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Operating Systems 301: Introduction to Advanced Concepts

So far we’ve looked at the most basic concepts in firearms operating mechanisms as part of the 101 series of posts, and some more advanced concepts like locking and bolt configuration in the 201 level entries. However, there is a whole lot more depth to the subject, so much that the advanced 301 level discussions will really only be able to scratch the surface. Before we start talking about these subjects though, be forewarned: So far I have avoided including any serious math in the 101 and 201 level posts, but we will have to tackle some math as we delve deeper into how these weapons really work.

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Operating Systems Omnibus 1: Tilting, Trapping, Recoiling

So far in our exploration of firearms operating systems, we’ve covered ten different mechanisms for locking and actuating an automatic firearm, with two supplementary introduction posts. There’s still a lot more to talk about, but at the request of our readers, I have decided to periodically collect posts together into an omnibus post, so that you the reader can easily access and share them!

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Operating Systems 101: API Blowback Operation

Previously on Operating Systems 101, we discussed the straight blowback method of firearms operation; today we’ll be talking about its close cousin, API blowback. “API” stands for advance primer ignition, which refers to the chief way that the mechanism differs from its pure cousin. We’ll get to that in a bit, but first we need to discuss the concepts of open bolt and closed bolt operation.

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Operating Systems 201: Ljungmann vs. Stoner Direct Impingement

In this 201-level post on the devices and mechanisms that automatic firearms use to do their work, we’ll be discussing a distinction between two very similar types of gas systems. These are what’s commonly known as the “Ljungmann-type” gas system (called so after a Swede, even though in reality a Frenchman invented it decades earlier) and “Stoner-type” gas system. Both are forms of what’s called “direct impingement”, a term which has two different meanings, one of which we’ll discuss today

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Operating Systems 201: Tilting Barrel Locking

Previously, we looked at the most common type of locking mechanism for rifles, but what about handguns? Well, today we’ll be looking at tilting-barrel locking, a method used in virtually every modern locked-breech handgun today.

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Operating Systems 201: Rotary Locking

We introduced you to the concept of locking in a previous one of our 201-level posts on how firearms work, and today we’re going to talk about what has become the most common locking mechanism for rifles: Rotary locking. If to lock an action, you need to create an interference between the breechblock and the barrel, one of the most intuitive ways to do this is the same way a barrel bolt latch works.

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Operating Systems 101: Short-Recoil

Two basic mechanisms dominate the field of handguns today: The aforementioned straight blowback system, and short-recoil operation. The latter of two is a mechanism as clever as it is old; the first short-recoil weapons date back to the latter half of the 19th Century!

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Operating Systems 101: Straight Blowback

The first entry in our coverage of automatic weapon operating mechanisms will be the humble straight blowback method. Conceptually simple, it is one of the most common systems, being applied almost universally to .22 caliber rimfire autoloaders the world over, as well as being very commonly applied to budget centerfire handgun and rifle designs.

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