Amazing video of 1,000,000 FPS bullet impacts.

[Crossroads Inc.]

Sometimes... Sometimes you want to just watch something that makes you go:
SCIENCE FUCK YEAH!

Well for those out there wanting a little "Fuck Yeah" I offer the following video:
(warning, the music might get a little repetitive after a while)
Among the things you shall see, aside from Bullets simply impacting into things, are.
Watching Primer cord explode slowly.
Bullets being hit by OTHER bullets in mid air.
Bullets being fired so they hit the edge of Armor and get Sheared in two, and keep going.
There is something about watching metal turn into what looks like GOO at super high speed that is almost hypnotic.

[Eternal_Freedom]

That's just awesome

[Borgholio]

Best parts : Bullet vs bulletproof glass - watching the cracks form in slow-mo is really neat. Also, bullets vs sloped armor vs a vertical plate. No wonder the military likes to use sloped armor on it's vehicles whenever possible.

[Zwinmar]

looks like they turn to liquid on impact.

[Batman]

Since when can we give bullets a velocity of 300KPS?

[Crossroads Inc.]

looks like they turn to liquid on impact.

I noticed that on a LOT of the impacts.
It made me wonder if perhaps Heat caused by friction or the force of impact causes a state change in the bullets?
I mean, a great deal of those impacts looked more like mud splattering then metal shrapnel.

[Simon_Jester]

Why does this give me a sudden urge to play World of Tanks?

[Dargos]

Since when can we give bullets a velocity of 300KPS?

1,000,000 Frames Per Second Video not Feet per second. Subject title is a bit confuseing.

[krakonfour]

Why does this give me a sudden urge to play World of Tanks?

[LaCroix]

looks like they turn to liquid on impact.

I noticed that on a LOT of the impacts.
It made me wonder if perhaps Heat caused by friction or the force of impact causes a state change in the bullets?
I mean, a great deal of those impacts looked more like mud splattering then metal shrapnel.

You should remember that apart from a thin casing of copper, most of the bullet is lead. If you take a .308 Win, you'll have ~10grams of lead sent off with an energy of about 3500J.

Lead has a specific heat of 131 J/(kgK), and a melting point of ~330°C -> which means that it takes about 450J to liquefy that core. Since a vertical plate of steel at point blank will eat up half of the muzzle energy, about 1750J will act on the bullet, and eyeballing it, the the core will be heated to about 1000°C, ignoring the initial temperature after exiting the barrel. At that temperature, lead acts like water. So it's actual molten metal flying around.

[Crossroads Inc.]

So basically we ARE Watching liquified metal splattering out like goo.
Thats fucking AWESOME.

Watching a lot of the early ones from 20 seconds onwards, the derbies going out is so fine it almost looks like mist.
It is also interesting to see the transfer of energy to the target itself. On a lot of these you can also see the side of the target buckle and the metal shatter under stress from the bullet.

[LaCroix]

Watching a lot of the early ones from 20 seconds onwards, the derbies going out is so fine it almost looks like mist.

Given that the vaporisation point is at roughly 1700°C, it is very much possible that a portion of the lead core's tip actually vaporizes on impact. The energy is there, it all hinges on thermal conductivity.

[Borgholio]

looks like they turn to liquid on impact.

I shoot black powder weapons for fun, and I recognized some of those shots as minieballs from a black powder musket. They are pure lead, no copper jacket or anything. I did see that the modern rounds with metal jackets did peel like a banana, but did better overall.

[krakonfour]

I wonder how much tungsten core AP rounds cost. They'd be fun to watch.

[krakonfour]

I wonder how much tungsten core AP rounds cost. They'd be fun to watch.

[Borgholio]

Why not just go with depleted uranium?

[krakonfour]

Why not just go with depleted uranium?

I think there are some legal issues with obtaining it.

[Borgholio]

Why not just go with depleted uranium?

I think there are some legal issues with obtaining it.

Same with tungsten-core armor piercing rounds.

[krakonfour]

Why not just go with depleted uranium?

I think there are some legal issues with obtaining it.

Same with tungsten-core armor piercing rounds.

Nah. Tungsten is sold at specialty shops, it just costs a lot. DU however can be used in the creation of low-grade salted bombs, which ruffles a lot of jimmies in the media business.

[Sea Skimmer]

In all reality DU is less radioactive hazard then the stuff in smoke detectors, or a bunch of other things you can buy like natural uranium which still has several percent U-235 in it. You can go buy DU if it you want, as long as it is a small amount, if you want a hundred pounds you need an NRC license, but making it into good ammunition would be a pain in the ass to say the least. Also tungsten and DU aren't all that great of AP materials without specific alloying, though certain grades of tungsten can be bought that are somewhere close to being correct.

At this point we have a far bigger concern with someone using DU to shield a dirty bomb, or nuclear bomb made from something else vs radiation scanners then using the DU as the bomb payload.

As far as the US goes making them into bullets for the purpose of armor penetration would be illegal, but it is legal to use it to increase the mass of hunting cartridges. Nobody much does that though, but its gaining attention with all the attempts to ban lead ammo. In fact the ATF put out a request for information on proposed factor made DU and tungsten hunting ammo (also other stuff) just recently as part of public comments on changing the restrictions on AP ammo to allow for a wider range of hunting loads.

So basically we ARE Watching liquified metal splattering out like goo.
Thats fucking AWESOME.

Nope, you really aren't. That's just the way metals behave under high pressure when striking a target harder then the metal itself. The very thin copper jackets peel off the lead cores in an elastic manner, aided by the centrifugal effect of the bullet's spin while the lead just explodes to pieces. This is functionally no different then bending a thin piece of metal in your hand and causing the joint to stretch and thin out. Except way faster and past the point of breaking. Its just fragmentation at work. Conventional small arms bullets will just structurally break up long before they can convert enough energy to heat to melt on a significant scale. Its a hail of dust, not vapor.

Very very small amounts of melting may occur depending on the velocity, bullet and target, but that's not primarily what you are seeing, I doubt its even one spec of what you are seeing.

Remember a shaped charge can squish copper out at ~8km/s, which is ten to twenty times faster then any of these projectiles would have been going, and still not melt it in the process. A metal's own insulating properties will limit is ability to melt under sudden high pressure. Its not just energy but time that matters when you get into microsecond scale self destruction. That's why something like a thin walled mortar bomb can explode with a hail of fragmentation and not a spray of liquid steel as well, and well, a thousand other examples.

[krakonfour]

Thanks, Sea Skimmer.