Japanese Sword spilts a Bullet

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Looney

Lifer
Jun 13, 2000
21,938
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Originally posted by: Shockwave
Originally posted by: Hardcore

Well, i don't claim to know a lot about physics... but i'm pretty sure there's a difference in force when you're shooting something head on vs glancing something so it can spin.

True, but even then this isnt "head on" as it were. A very good deal of the energy is still present even after contact with the sword, visible by the holes in the paper. The sword doesnt STOP the energy, it just redirects it as it were. Now, if they turned the sword sideways and then shot it, thats a different story, as the blade would then have to stop ALL the energy of the bullet, not just cut the bullet and redirect the energy.

Even if it shot at a wall, there would still be some ricochet and debris. But i can guarantee you the force of that bullet directly on the sword blade was more than a bullet that goes through rifling.
 

Shockwave

Banned
Sep 16, 2000
9,059
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Originally posted by: Deadtrees
Originally posted by: Shockwave
Originally posted by: Hardcore

Well, i don't claim to know a lot about physics... but i'm pretty sure there's a difference in force when you're shooting something head on vs glancing something so it can spin.

True, but even then this isnt "head on" as it were. A very good deal of the energy is still present even after contact with the sword, visible by the holes in the paper. The sword doesnt STOP the energy, it just redirects it as it were. Now, if they turned the sword sideways and then shot it, thats a different story, as the blade would then have to stop ALL the energy of the bullet, not just cut the bullet and redirect the energy.

Ok, now it seems like we're back on the topic. I do agree with you on the 'siding the sword' issue.
I'm thinking 'any decent' sword with change the shape due to the impact. I'm not here proving I'm right and you're wrong. I'm here because I don't really know and want to know.

Some swords would. The test DOEs show the sword has a strong edge, but I'd like to see a close up shot of where the bullet impacted before I really make that call. My ground is simply saying most good steel sharpened to a edge and not having a good deal of thickness would pass this test. Now, how the edge holds up is the true worth of the steel. Hell, he could turn the blade around and fire at the back and I'll bet most any commercially available steel would still hold up to the impact, although the edge may deform some.
The problem is, theres a TON of varieties of steel. So, we cant just say "steel" without getting into a look of the composition of the steel. Theres high carbon, low carbon, plated, theres heat treated etc etc etc.
 

Deadtrees

Platinum Member
Dec 31, 2002
2,351
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Originally posted by: Shockwave
Originally posted by: Deadtrees
Originally posted by: Shockwave

Ummm, ever hear of rifling? You DO know what rifling does right? Rifling actually does EXACTLY what that sword does. It cuts into the bullet to give it spin. So yes, gun barrels are shot into every day thousands of times with no adverse affect.
Look, its a cool video, and shows the quality of good steel, but its certainly nothing to get all googly eyed about.

Rifling is there for accuracy and distance, not even for the impact. A sword works totally different way. I don't even know why you're talking about the 'melting' issue and 'spin'. Hello? The subject here is the 'impact'.

The point is barrels last practically FOREVER. The point is, rfiling does what that sword does. It cuts into the bullet. You think rifling is there for looks? How do you think it makes the bullet spin? BY ENGAGING THE BULLET! BY CUTTING INTO IT!! My point about heat is THATS what usually causes barrels to fail, too much HEAT produced by the POWDER. HEAT wears out barrels, NOT the bullet tearing down the rifling. Same with the sword. The sword CUTS the bullet, much like rifling!!
The point of heat is only to show what usually wears out a barrel is heat, and since theres no real amounts of heat in the sword vs bullet, I'm not really suprised.
And "impact" isnt even much of an issue. Did the sword stop the bullet? No. Proof is in the paper with holes still in it. The sword isnt stopping the bullet, that bullet still has ALOT of energy left. The sword simply cut the lead bullet into 2 peices and they continued on there way.

Again, I'm not trying to lessen the sword itself, just saying theres far better tests in MY mind to proof the worth of the sword besides splitting lead.

Rifling 'cuts into' the bullets? Maybe, it's the expression I'm not used to and that it has a different meaning than what the words suggest. There's a difference smacking a basketball directly with a hammer and spinning it with a hammer. Any good blade would loose its tooth once it gets the 'impact' from a kind of solid(or near solid) object.
 

Shockwave

Banned
Sep 16, 2000
9,059
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Originally posted by: Hardcore


Even if it shot at a wall, there would still be some ricochet and debris. But i can guarantee you the force of that bullet directly on the sword blade was more than a bullet that goes through rifling.

Absolutely, I wont argue that point. But the point is, the rifling does it for thousands and thousands and thousands of rounds without fail, BECAUSE its steel and holds up so well to stress. People even use steel as penetration tests, ranging from 1/4" to 3/4" in thickness. Steel is very, very hard to penetrate with any bullet under a .50 caliber round, and even then it takes a specially designed "armor piercing" core to really get penetration.
 

Kilgor

Diamond Member
Oct 10, 1999
3,292
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Originally posted by: Hardcore
Originally posted by: Shockwave
Originally posted by: Hardcore

Well, i don't claim to know a lot about physics... but i'm pretty sure there's a difference in force when you're shooting something head on vs glancing something so it can spin.

True, but even then this isnt "head on" as it were. A very good deal of the energy is still present even after contact with the sword, visible by the holes in the paper. The sword doesnt STOP the energy, it just redirects it as it were. Now, if they turned the sword sideways and then shot it, thats a different story, as the blade would then have to stop ALL the energy of the bullet, not just cut the bullet and redirect the energy.

Even if it shot at a wall, there would still be some ricochet and debris. But i can guarantee you the force of that bullet directly on the sword blade was more than a bullet that goes through rifling.

Why would you say that? The impact point on the blade is most likely razor sharp and the rifling is just cut steel.
 

Deadtrees

Platinum Member
Dec 31, 2002
2,351
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Originally posted by: Shockwave
Originally posted by: Hardcore


Even if it shot at a wall, there would still be some ricochet and debris. But i can guarantee you the force of that bullet directly on the sword blade was more than a bullet that goes through rifling.

Absolutely, I wont argue that point. But the point is, the rifling does it for thousands and thousands and thousands of rounds without fail, BECAUSE its steel and holds up so well to stress. People even use steel as penetration tests, ranging from 1/4" to 3/4" in thickness. Steel is very, very hard to penetrate with any bullet under a .50 caliber round, and even then it takes a specially designed "armor piercing" core to really get penetration.


But I can make the rifling to loose 'its tooth' if I hit it directly with an object.
Hmm...I gotta ask about this issue to a gun techician I used to work with.
I'll post what he says about this issue. Until then, I'm clueless.

BTW, rifling vs. impact the sword is getting from a bullet is a totally different issue.
A gun barrel is NOT designed to impact the bullet directly; it barely touches the bullet and that's why a barrel is the part that's hard to make(and this is why many people can personally make shotguns(doesn't have rifling).
 

Shockwave

Banned
Sep 16, 2000
9,059
0
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Originally posted by: Deadtrees
Originally posted by: Shockwave
Originally posted by: Hardcore


Even if it shot at a wall, there would still be some ricochet and debris. But i can guarantee you the force of that bullet directly on the sword blade was more than a bullet that goes through rifling.

Absolutely, I wont argue that point. But the point is, the rifling does it for thousands and thousands and thousands of rounds without fail, BECAUSE its steel and holds up so well to stress. People even use steel as penetration tests, ranging from 1/4" to 3/4" in thickness. Steel is very, very hard to penetrate with any bullet under a .50 caliber round, and even then it takes a specially designed "armor piercing" core to really get penetration.


But I can make the rifling to loose 'its tooth' if I hit it directly with an object.
Hmm...I gotta ask about this issue to a gun techician I used to work with.
I'll post what he says about this issue. Until then, I'm clueless.

Neither the sword nor rifling are "directly" hit really. I mean, essentially the rifling is directly hit due to the bullet not engaging the rifling until after its has started to travel. Engaging the rifling before it has been fired is DANGEROUS and could cause your gun to explode!! So, theres always a bit of dead space between the bullet and the rifling to get the bullet moving before slamming into the rifling. Granted, its not inches deep, but the rifling does make contact with the bullet.
Same with the sword. Thats why i use a reference to rifling. The bulelt is getting cut by the rifling, the bullet is getting cut by the sword. Again, if they sword was turned wideways so it actually was fully impacted by the bullet, then thats a different story. But as it is, the blade is what, 1/4 of the thickness of the bullets diameter? So, theres no way the sword could absorb the entire impact of the bullet.
 

Shockwave

Banned
Sep 16, 2000
9,059
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I think your confusing impact with cutting. While the bullet DOES impact the sword, it doesnt "impact" it in the way a normal bullet would and dump the energy into the target. Bullets are designed to impact something that can absorb their energy and cause them to mushroom. Something larger then the bullet is, that way ALL the energy is dumped into the target. In this case, the sword is narrower then the bullet, so even best case scenario the bullet couldnt possibly dump all the energy it has contained into the target (the blade). So right there the video is skewed, as the sword doesnt get the full eenrgy of the bullet. Secondly, lead (The bullets composition (mainly, some copper)) is notoriously soft and weak. Steel on the other hand is usually noted for its hardness. Worked, conditioned steel can be wicked hard AND still flex so as to not be brittle. Think of this as cutting cardboard with a knife. While both substances are hard (Ever get hit with a cardboard tube?) the knife is vastly harder then the cardboard.
 

Deadtrees

Platinum Member
Dec 31, 2002
2,351
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Originally posted by: Shockwave

Neither the sword nor rifling are "directly" hit really. I mean, essentially the rifling is directly hit due to the bullet not engaging the rifling until after its has started to travel. Engaging the rifling before it has been fired is DANGEROUS and could cause your gun to explode!! So, theres always a bit of dead space between the bullet and the rifling to get the bullet moving before slamming into the rifling. Granted, its not inches deep, but the rifling does make contact with the bullet.
Same with the sword. Thats why i use a reference to rifling. The bulelt is getting cut by the rifling, the bullet is getting cut by the sword. Again, if they sword was turned wideways so it actually was fully impacted by the bullet, then thats a different story. But as it is, the blade is what, 1/4 of the thickness of the bullets diameter? So, theres no way the sword could absorb the entire impact of the bullet.

What you're saying does make (not enough) sense, at the same time, what I'm saying only makes (not enough) sense, too.
I'll keep myself quite until I get the answer from the professional.
 

BadNewsBears

Diamond Member
Dec 14, 2000
3,426
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Originally posted by: Shockwave
Originally posted by: Deadtrees
Originally posted by: Shockwave

I said "decently made" which implies a good steel. Good steel wont even flinch to a bullet. A prime example is a gun barrel. Its simple 5140 (or 4150) steel. Its not the bullets that burn out barrels, its the heat from the powder.
So, gun barrels (steel) hold up to thousands of rounds. Why shouldnt a good sword (steel) hold up to one.

Now, those cheap 100 dollar display models... Your milage may vary there, because I'm sure they use a softer steel or a more brittle steel. Essentially, they dont use the RIGHT steel.

Also, it's not just about the gun powder. You can shoot a machine gun hundreds and thousands times more (without changing the barrel) if you used a blank bullet. It's because the bullet generates much heat passing through the barrel. Well, that was my experience from shooting M60 with blank bullets and real bullets(As I was a Former SAW, granade launcher(Don't know the correct term in English), Special Forces squad leader)
Anyway, the issue here is the 'impact' not the 'heat'. I don't know why you're talking about the heat issue.
(Do you think the poorly made sword would melt?)

Ever burn the throat out of a .243? Its due to the case neck being so short that some of the buring powder gets intot he barrel and slowly eats it away.
I'm only talking about heat in a very few select calibers in terms of not doing belt dumps (running thousands of rounds through them and melting barrels)

Dont misconstrue what I'm saying. I'm not trying to detract from the quality of the sword. I'm simply saying, it isnt JUST because its a Hatori that it can split a lead bullet.


Dont forget FPS. The faster the bullet moves the faster the barrel goes to hell.
 

Shockwave

Banned
Sep 16, 2000
9,059
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Like I said, not detracting from the sword, Its definately VERY good steel (Watched the whole video) cause on the close ups at the end you can see the blade, and more precisely, the edge, didnt fold or lose shape. So, its definately good steel, but I'd like to see how well it held up to a Claymore wielded by a pissed of drunk Scotsman.
Think of it like this.
Pop can = bullet
Table knife = sword

pop can vs pop can. (bullet vs bullet) and with even moderate force, they both essentially destroy each other. Both will shows marks from a head on confrontation.

Pop can vs Table knife. (bullet vs sword) The table knife wins every time. You can stab and chop and swing all you want, but you wont really do much aside from mar the finish on the table knife, because the pop can is just so much softer. Same with a sword vs bullet

table knife vs table knife. (sword vs sword) This is where you find the true mark of a blade. Countering an equally hard object with another equally hard object, especially if weilded with much force, you'll soon see which one really has the extra degree of quality. The lesser will lose shape and dull quickly, the higher quality one will hold its shape and edge longer and through more forceful blows. A true test of edge IMO is to use another quality sword, give it to two people and have them try to kill each other for 5 minutes. Then see which edge is still the sharpest with the least deformation. So, think of two swords slamming into each other, edge vs edge. Both are very hard. But, SOMETHING has to give. It might be the edge, it might be the blade or it might be the other guys balance as he backpedals to recover from the force. But, if you can repeatedly do this and the edge holds strong, you have a GOOD sword.

A disclaimer though, hardness and brittleness go hand in hand with steel (usually) Thats why I'm not saying the sword is any less in quality. While the bullet may be soft and easily cut by the hardest of materials, a brittle material would shatter from the shock. Think if that sword was glass? The bullet would shatter it to peices. So, the sword has to have both hardness to hold and edge and remain sharp, but also be soft enough to absorb impacts and flex so as to not shatter. With heat treating, tempering and proper forge work you can actually make blades that have bands and layers of varying degrees of softness and by mixing them get a best of both worlds as it were, having a blade thats both very hard and able to absorb impact.

But, thats why this test doesnt weigh too heavily with me. The bullet is just too soft. Go blow for blow with another peice of steel, THEN let me see the edge. If it can hold up to another steel blade, then you have a fine weapon.
 

Deadtrees

Platinum Member
Dec 31, 2002
2,351
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Now, I'm more convienced toward your theory, but I still have a doubt.
I'll let you know once I get the words from the techician (I think he'd basically say the same thing as you though).
 

zimu

Diamond Member
Jun 15, 2001
6,209
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trust ATOT to get into a super in depth discussion about a stupid video clip. nah, nobody wants to just watch the clip, say "cool clip!" any more. nowadays you have to argue about metallic properties, spinning bullets, lifespan of barrels and god knows what.

jeeze guys. chill out a bit once in a while. i'm sure all of you know a lot about this stuff, but seriously- what are you achieving by this whole shpiel??
 

Shockwave

Banned
Sep 16, 2000
9,059
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Originally posted by: zimu
trust ATOT to get into a super in depth discussion about a stupid video clip. nah, nobody wants to just watch the clip, say "cool clip!" any more. nowadays you have to argue about metallic properties, spinning bullets, lifespan of barrels and god knows what.

jeeze guys. chill out a bit once in a while. i'm sure all of you know a lot about this stuff, but seriously- what are you achieving by this whole shpiel??

Simply pointing out (In my mind) there would be more effective ways to demonstrate the strength of a sword.
 

DJFuji

Diamond Member
Oct 18, 1999
3,643
1
76
Am i the only one who noticed the post about this bullet being titanium coated with a diamond core? Everyone keeps talking about how this is an easy feat because its just soft lead being split by a sharp edge. I think ANYTHING that splits a round like that is impressive.
 

Shockwave

Banned
Sep 16, 2000
9,059
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Originally posted by: DJFuji
Am i the only one who noticed the post about this bullet being titanium coated with a diamond core? Everyone keeps talking about how this is an easy feat because its just soft lead being split by a sharp edge. I think ANYTHING that splits a round like that is impressive.

Yes, but chose to ignore it based on its complete and utter stupidity.
 

Pacfanweb

Lifer
Jan 2, 2000
13,158
59
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Originally posted by: BaboonGuy
Originally posted by: Shockwave
That feat should be relatively easy for ANY decently made sword. Espeically using pistol ammunition. Pistol bullets are lead, you can actually "cut" then with a good butterknife. I've made many a homemade hollowpoint by taking a pocket knife and cutting a deep X into the tips.

true, IF it was a regular bullet. i speak japanese, in the opening parts, they explain the bullet is special made: titanium casing with a diamond core.
So? None of the titanium or diamond was shot at the sword. Only the lead. The casing is irrelevant...it could have been made out of Kryptonite and it wouldn't have made any difference.

My question would be: Who give a crap if a sword is that tough or not? What the hell does anyone plan to do with it that they felt the need to prove how strong it is?
 

Klixxer

Diamond Member
Apr 7, 2004
6,149
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So, a sharp blade will cut a bullet every time.

Most of you have guns, try this, get a regular steel, not hardened or anything, sharpen it up and create a dual angled blade with a sharp edge, now fixate the blade and the gun, shoot and then look at the blade.

The short barrel of a handgun and the fairly large ammunition makes the test useless, let's see it with a .30-06 shot from a rifle.

A hot tip is that it would break the sword in half. The redirection of energy isn't nearly efficent enough (even from a very sharp blade) to withstand the impact of a high powered rotating copper casing bullet.

The titanium and diamond core, well, i call BS on that, a diamond core would break the steel. If it didn't, then there would be no way to sharpen that steel.
 

Klixxer

Diamond Member
Apr 7, 2004
6,149
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Originally posted by: Pacfanweb
Originally posted by: BaboonGuy
Originally posted by: Shockwave
That feat should be relatively easy for ANY decently made sword. Espeically using pistol ammunition. Pistol bullets are lead, you can actually "cut" then with a good butterknife. I've made many a homemade hollowpoint by taking a pocket knife and cutting a deep X into the tips.

true, IF it was a regular bullet. i speak japanese, in the opening parts, they explain the bullet is special made: titanium casing with a diamond core.
So? None of the titanium or diamond was shot at the sword. Only the lead. The casing is irrelevant...it could have been made out of Kryptonite and it wouldn't have made any difference.

My question would be: Who give a crap if a sword is that tough or not? What the hell does anyone plan to do with it that they felt the need to prove how strong it is?

Pretend they are samurais and jump around in their gardens wearing a silly outfit swinging the sword?
 

Shockwave

Banned
Sep 16, 2000
9,059
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Originally posted by: Klixxer
So, a sharp blade will cut a bullet every time.

Most of you have guns, try this, get a regular steel, not hardened or anything, sharpen it up and create a dual angled blade with a sharp edge, now fixate the blade and the gun, shoot and then look at the blade.

The short barrel of a handgun and the fairly large ammunition makes the test useless, let's see it with a .30-06 shot from a rifle.

A hot tip is that it would break the sword in half. The redirection of energy isn't nearly efficent enough (even from a very sharp blade) to withstand the impact of a high powered rotating copper casing bullet.

The titanium and diamond core, well, i call BS on that, a diamond core would break the steel. If it didn't, then there would be no way to sharpen that steel.

Actually, even if it WAS diamond core I think the results would have been very similiar. Diamond is notoriously hard. Its also very brittle. That type of impact most likely would have shattered a diamond. Additionally, I dont believe titanium to be that much harder then steel to the point a titanium casing would cut the steel. Although titanium IS harder then steel by a good margin, the outer jackets of bullets are so thin (a few thousanths) that there just isnt enough material to overcome the steel.
 

Klixxer

Diamond Member
Apr 7, 2004
6,149
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Originally posted by: Shockwave
Originally posted by: Klixxer
So, a sharp blade will cut a bullet every time.

Most of you have guns, try this, get a regular steel, not hardened or anything, sharpen it up and create a dual angled blade with a sharp edge, now fixate the blade and the gun, shoot and then look at the blade.

The short barrel of a handgun and the fairly large ammunition makes the test useless, let's see it with a .30-06 shot from a rifle.

A hot tip is that it would break the sword in half. The redirection of energy isn't nearly efficent enough (even from a very sharp blade) to withstand the impact of a high powered rotating copper casing bullet.

The titanium and diamond core, well, i call BS on that, a diamond core would break the steel. If it didn't, then there would be no way to sharpen that steel.

Actually, even if it WAS diamond core I think the results would have been very similiar. Diamond is notoriously hard. Its also very brittle. That type of impact most likely would have shattered a diamond. Additionally, I dont believe titanium to be that much harder then steel to the point a titanium casing would cut the steel. Although titanium IS harder then steel by a good margin, the outer jackets of bullets are so thin (a few thousanths) that there just isnt enough material to overcome the steel.

Doesn't matter, if it had a diamond core it would break the steel, steele hardened to this level is more brittle than diamond and the diamond would be harder.

The amount of the material does not matter unless it is real thin and hits flat on, in this case the material impacts with the SAME AMOUNT of material and the weaker material will break.

I am having a hard time believing a titanium casing too, the titatium wouldn't be cut, it would be shattered.
 

gururu

Platinum Member
Jul 16, 2002
2,402
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this titanium/diamond business is nonsense. if anything they were using a black diamond titanium riflescope. ;)

anyways, the bullet is soft lead and even 'softer' after while in motion because of both heat and kinetic energy. thats why hollow points explode simply by having flesh crammed into their center. Shockwave is probably right that most sharp edged steel will split a bullet, just as any good sword will cut through a 9mm diameter lead rod with sufficient direction and force. finer swords would no doubtedly hold up better. Heat up that lead rod to 267 C
and even weaker swords will remain flawless.
smme like a cool vid though. I couldn't get it to play ;(