Sonoluminescence in ballistics gel


#1

Originally published at: http://boingboing.net/2016/09/15/sonoluminescence-in-ballistics.html


#2

That was cool. And I also highly enjoyed the amount of clear gel jiggle.


#3

Really really cool! But it isn’t sonoluminescence. It’s combustion due to adiabatic compression of a fuel air mixture. Similar to the diesel cycle. A totally cool way to cause it too.
Here’s the same phenomena using cotton and a syringe:


#4

That’s what I thought… the flash is clearly accompanying an explosion which fuels a secondary expansion of the gel. I’m just wondering if a similar effect can also happen in tissue…


#5

What is the fuel in this case? The gel?

I’ve never seen gel tests look quite like that with the flash. It also seems a bit more wiggly and clearer than usual which makes me wonder if it isn’t as firm as the gel I am used to seeing, but there is more than one type of gel.


#6

Mistakenly thinking this is related to sonoluminescence is a common error.

The newly popular synthetic clear ballistic gel is much more flammable than living tissue. I’ve noticed that this and similar videos always use a clear gel (e.g. ClearBallistics), not the more traditional translucent organic ballistic gelatin.


#7

I almost felt sorry for the gel.


#8

Just think - a bullet does just the same thing inside of you!


#9

Let’s watch!


#10

Sort of. Ballistics gel emulate the density of tissue, but it isn’t a perfect emulation. How stretchy parts of the body are and how connective tissue and your skeleton holds things together means that even though there is a wound channel, it isn’t the same as with the gel.

I can’t find a video of it but mythbusters shot a pig carcass balanced on a hook with a .50 BMG, and not only did it not fall off the hook, (dispelling the myth that bullets can knock you back), but it just zipped through IIRC. Granted it was probably a FMJ, but if you look at this video of shooting 2 blocks with a .50 BMG, it shreds it apart.

Also they must be using the same gel as it too has a spark and is clear.


#11

The wikipedia page for sonoluminescence has a similar video.


#12

Pootpootpootpootpoot.


#13

Pity such phenomena isn’t confined to ballistic gel


#14

Did that gel just let one rip?


#15

Yes the gel. From the faq on http://clearballistics.com/faq/ it sounds like the stuff is pretty much made out of petroleum, seeing as it doesn’t mold or rot, supposedly is “inorganic” (but much cheaper than any silicone I’ve ever seen) and so forth.

So why shouldn’t it burn at appropriate temperatures or pressures? Besides that, after the flash, there’s a prodigious amount of smoke coming out of the entry hole, suggesting the flash was combustion. Additionally, the flash was orange, instead of white, suggesting it came from the combustion of organic molecules, and not a sonoluminescence flash which tend to be much closer to white or blue.


#16

Man, the Barret’s action is noisy. Do you watch Demolition Ranch or TAOFLEDERMAUS? They’re pretty interesting too. I like the cut of this guy’s jib too. Very safety aware. .50 BMG should be called .50 BFG. It’s a round you don’t mess around with.


#17

What’s with the music?

I kept expecting the ballistics gel to jump off the log and cable drop into a maximum security facility so it could steal the secret access data on a thumb drive.


#18

Looks like there’s a huge misconception among gun users that this is sonoluminescence and it spilled into Wikipedia. But I’m too lazy to edit.

In every ballistic gel video, it’s the wrong size, shape, and color to be sonoluminescence. The smoke is a dead giveaway that this is combustion. Another giveaway is that sonoluminescence last 30-35 picoseconds per contraction. If you see light on more than one frame of video, it’s something else. It appears to last longer in the real thing because the bubble is expanding and contracting thousands of times per second due to a standing ultrasonic wave.


#19

OH I want to mess with… I just don’t have access to one or an area to use it. Friend in TN has one. Someday…

I wouldn’t want to use it indoors or even under that covered range. As Miculek said, you can really feel the blast from the muzzle break. That is annoying enough on a .308. Even a .223/5.56 is annoying if you aren’t right behind it, but to the side.

Thanks for the info on the gel. I too saw the smoke, so yes, it did look like a combustion. I think ACE above made similar comments. Learn something new every day.


#20

Poor old gel.