Subtitles section Play video
Hey it's me Destin. Welcome to this week in Smarter Every Day. Today we're gonna try to figure
something out that I've always wondered. What happens when you shoot a pistol
underwater. I think revolvers are gonna act a little different than semi-automatic pistols.
[music]
Alright, here we are in the field, this is the setup. So what we have here is a revolver
in an aquarium that we made out of plate glass and silicone. This should be
pretty cool, but we're gonna film this with this Phantom v10
camera made by Vision Research. We're gonna film it at 2200 frames per second.
We've got about a 40 microsecond exposure time. But in order to get enough light we have to
use this, which is a 15 million candle power spotlight.
This should be pretty cool, but the intent here is we're gonna fill this up with water
over the pistol, and we're gonna see if we can capture that gas bubble as it comes between
the revolver and the barrel. It should expand, and hopefully not blow up.
But I'm expecting this to blow up. And immediately after we capture all that
video we're gonna compress it into a pretty small format and then we're gonna
beam it via this satellite dish straight to the 80s so that my granddad can.. I'm just kidding.
Anyway, let's do the shot.
[music]
Do I look as sad as I feel? [laugh]
Or maybe nervous? I really don't want this to blow up
because I don't have money to buy it again if it does, so...
I'm doing this so you can learn. You don't have to blow your pistol up.
[music]
Alright, let's see if she lived. I really hope so.
3..2..1.. [bang]
Yay Ruger. Alright so now let's talk about the results.
To my knowledge this is the first time handguns have been studied like this, and there's
obviously a lot of stuff to learn here but I'll focus on three things that are pretty simple.
The first thing is, it was pretty clear that as soon as the hammer
struck the firing pin which hit the primer, there was an outgassing, you could
actually see a bubble. It's pretty interesting. My assumption is that
that's the seal around the primer breaking down and causing a little outgassing.
Nothing really new there. The second thing that we learned is it appears that
the semi-automatic pistol is more efficient at applying the gases generated by the cartridge
to the back of the bullet creating more velocity than the revolver.
You noticed when the revolver fired there was this large blast wave
that came out from between the revolver cylinder and the barrel. All that is
wasted energy that could be applied to increasing the velocity of the round, which wasn't.
So that was also pretty interesting. The next thing that we learned
is when the weapon is fired, you see this large blast
wave come out the front of the weapon. Now the assumption is, or at least the assumption
I made to begin with is that it's a spherical blast wave. It's actually
not. It's more like a bagel or doughnut.
It's what's called a toroidal vortex. Root word being
torus. So if you were to take this
and... let me draw this... alright.
So this is kinda what's happening here. The gases are coming out
from the barrel, and they're going in a loop around
the outside of the bullet. Toroidal vortex, that's what's going on there.
Anyway, there's a whole lot to learn here. I hope you're getting Smarter Every Day.
Have a good one.
[music]
[ Captions by Andrew Jackson ] captionsbyandrew.wordpress.com
Captioning in different languages welcome. Please contact Destin if you can help.