What can katana cut - mythbusting and fact checking

Welcome to our myth-busting and fact-checking journey as we delve into the world of the legendary Japanese sword - the Katana. There are countless tales and misconceptions about what a Katana can cut through. From slicing through machine gun barrels to effortlessly severing other swords, the Katana has been attributed with almost magical abilities. But what’s the reality behind these claims? Let’s separate fact from fiction and explore the true cutting capabilities of this iconic weapon. Buckle up, as we’re about to slice through the myths and reveal the hard-hitting facts.

Table of Content

• Can a katana cut through bone
• Can a katana cut a bullet
• Can a katana cut a head off
• Can a katana cut through rock
• Can a katana cut a person in half
• Can a katana cut through a gun barrel
• Can a katana cut through a skull
• Can a katana cut through a tree
• Can a Katana cut through helmet? 

Can a katana cut through bone

Yes, a Katana can cut through bone. Its design is specifically tailored for the efficient cutting of flesh and bone, thanks to its harder edge and softer spine that absorbs shock. The cutting prowess of a Katana comes from the hardness of its edge, the unique geometry of the blade, its weight, velocity, and the sharpness it maintains.

There are many tameshigiri (cutting test) video online of katana cutting through bones, ribs, most modern steel like high carbon steel, T10 steel, with proper sharpness, and correct cutting skill, you can easily cut through bones with katana.

Reference: Cold Steel Dragonfly katana, made of 1055 carbon steel, cut thought a pig without problem.

Can a katana cut a bullet

Yes a a katana can cut a bullet, If the katana was securely fixed, and we shot the bullet right toward the edge. The reason is most bullet are made of lead, lead has a lower hardness (1.5) compared to stainless steel (4-4.5) and hardened carbon steel (8). When the bullet hits the steel, it is “cut” or broken due to the steel’s higher hardness.

The impact of the bullet is also influenced by the part of the blade it hits - the edge, which is the smallest, strongest, and hardest part. The speed and trajectory of the bullet amplify its force, and the small area of impact means the bullet will not win, especially against the thinner edge of a katana.

The test from Forged in Fire shows a katana is capable of slicing bullets from pistol.

Another test proves katana can slice bullet shooting at the edge

But if you want to hold a katana and stop a bullet, that will be impossible. The velocity at which bullets move makes it an impossible task for even the most skilled swordsmen to hit accurately. Some popular "katana vs bullet" tests, the trajectory is fixed and the performer can already predict where the bullets are before he draw the sword, it's very impressive that they could slice the bullet, but we don't think that counts.

Can a katana cut a head off

Absolutely yes, a Katana can cut a head off. Historical records highlight Samurai collecting heads as trophies to mark their victories in combat. Also in the famous suicide ritual Seppuku, after the samurai slice his belly with tanto, his kaishakunin will use a katana to cut his head off to end his pain.

Technically a good kaishakunin didn’t cut the head completely off, the best practice is to cut half the neck, and leave some skin to still connect the head to the body. All this should be done quickly to help end the pain and keep the respect, this is called “daki-kubi.”

Can a katana cut through rock

Tanjiro fans out there might be disappointed, but unfortunately you can not cut through a rock with a katana. In the anime Demon Slayer, in the final testing before joining Demon Slayers, Tanjiro sliced a boulder with a sword and pass the test. This is actually based in a Japanese myth "Ittouseki" ( 一刀石 One-cut Rock). This is a massive rock, about 8 meters in length, 7 meters in width, and 2 meters in height. This rock is said to bear the trace of a swordstroke—a vertical, straight crack in the center—cutted by the master swordsman Yagyu Muneyoshi 柳生宗厳. 

This is just a myth, but if you want to see this rock, it's in Tenshikidate Shrine in Nara Prefecture.

Can a katana cut a person in half

Yes, a katana can cut a person in half, as matter of fact, this is called tameshigiri and it is how the ancient Japanese test the katana quality. They use bodies of executed criminals, bodies were positioned on a sand mound and secured with bamboo stakes. The tester, wear a kami shimo and armed with a blade set in a unique iron-bound hilt, would then analyze the corpse to determine the most suitable cut from his array of techniques.

The difficulty of the cuts varied. For instance, a cut at the wrist was deemed the simplest, while a cut across the hips, known as ryo kuruma, or a diagonal cut through the shoulder girdle, referred to as o kessa, were considered the most challenging. Following the cut, the body and the blade were meticulously inspected for any damage and signs of clinging fat. If the tester was satisfied, he might proceed with more complex cuts.

Thought out history, over 20,000 katana were used for tameshigiri and their results were record on books "懐宝剣尺" (Kaihō Kenjaku) and "古今鍛冶備考" (Kokon Kajibikō). A katana with excellent sharpness is called "業物" (wazamono), based on their tameshigiri performance their smiths were ranked as:

最上大業物: Saijō Ōwazamono (Supreme Grade Wazamono): 15 smiths who forged swords with the highest sharpness.

大業物: Ōwazamono (Great Wazamono): 21 smiths who forged swords with sharpness ranking just below Saijō Ōwazamono.

良業物: Ryōwazamono (Good Wazamono): 58 smiths who forged swords with sharpness ranking below Ōwazamono.

業物: Wazamono (Wazamono): 93 smiths who forged swords with sharpness ranking below Ryōwazamono.

Additionally, 68 smiths who forged various grades of Ōwazamono, Ryōwazamono, and Wazamono are mentioned, bringing the total to 255 smiths.

The outcomes of these tests were engraved in gold on the tang of the katana(nakago).  For example, a record exists of a short sword blade by Nagasone Okisato Nyudo Kotetsu, which had the test result of cutting through two bodies engraved in gold.

In the case of exceptionally superior swords, multiple bodies were sometimes bound together. The record for this is a sword that managed to cut through the spines of seven stacked bodies.

Can a katana cut through a gun barrel

No, a katana cannot cut through a gun barrel. Steel is just a material and doesn’t possess any extraordinary magic power. Although a katana has the capability to cut a head or a limb with relative ease, it would only manage to slightly scratch a machine gun barrel. Real life is not anime, sorry guys.

Can a katana cut through a skull

Yes, a katana can cut through a skull. Skulls are hard, but a good katana with proper cutting skill can still cut through them, there is a similar tameshigiri practice is to cut kabuto (helmet) from samurai armor. In ancient Japan, katanas are made of tamahagane, it’s a precious iron but the performance isn’t as good as modern steel. So it will need a really blade smith for forge a good blade that can cut through skull. But with modern steel it’s much easier.

Can a katana cut through a tree

Yes, a katana can cut through a tree, particularly softwood saplings, small branches. However, it’s important to remember that the sapling’s diameter should not exceed 3 inches and the alignment of the blade’s edge needs to be precise. If the edge alignment is off, the katana might become bent, especially for carbon steel blades. The composition within a tree, which is very different from human flesh and bone, tends to compress against the blade as it penetrates deeper, and any sideways motion could lead to the blade bending.

And always remember clean your katana after every cut, the tree sap will rust the blade faster than you thought. Katana is a practical weapon with high aesthetic value, certain level of maintenance is required.

Can a Katana cut through helmet? 

Yes, this is a difficult task, tremendous amount of sword skill is required, but yes, a katana can cut through samurai armor helmet (Kabuto). 1997, In this performance, shows a katana can cut deep into the kabuto.

Modern Katana Cutting Targets

As mentioned, a katana is capable of cutting through many things. But for actual using, popular targets for testing the sword and its wielder's skill include tatami mats, water bottles, and pool noodles.

Tatami mats, called 巻藁 in Japanese, are the traditional test-cutting target, still used in today's tameshigiri practice and competitions. These mats are traditionally made from rice straw or rush grass, rolled, tightened, and then soaked in water. The Japanese believed that this material closely resembled the density of fresh human tissue, making it an excellent choice for testing cutting ability.

Water bottles and pool noodles are considerably newer and popular among sword enthusiasts outside of Japan because they are readily available and inexpensive.  While cutting water bottles filled with water is relatively easy, cutting empty water bottles is actually much more difficult and requires considerable skill.

In conclusion, we’ve journeyed through the myths and realities of the Katana’s capabilities. From cutting through bone and severing heads, to its limitations against bullets and gun barrels, we’ve explored the true power of this iconic weapon. Remember, while a Katana can cut through certain objects, it requires precise handling and maintenance. This legendary sword is not just a weapon, but a symbol of honor and discipline.