Muzzle Flash Tutorial w/ VSauce = Guns + Science Smarter Every Day 43

Uploaded by destinws2 on 20.02.2012

Hey it's me Destin. Welcome back to Smarter Every Day. So ah
first things first, let me show you that this weapon is unloaded. And I really like to
think about firearms because there's a lot of science involved here. What causes muzzle
flash. Alright number one. We have powder inside the cartridge that's
burning, that gas is expanding. It has to overcome the bullet to barrel friction
here, in the barrel, and it has to accellerate the mass of the bullet,
while pushing out the column of air that was inside the barrel. There's a lot of science there.
So, muzzle flash is affected by the cartridge load and the barrel
length if you think about it. Another thing that comes into play for muzzle flash
is the geometry of the exit. Now, this is just a plain right circular
cylinder so you get a toroidal vortex, but if you think about something like this,
you've got a fluted exit here at the muzzle you'll get more of a starburst pattern.
Over the past year I've been playing around and I have perfected I think a way of taking muzzle flash
photos. It involves this, which is a piezoelectric transducer
mounted to a wooden box, and I use that to convert acoustic energy to
an electrical pulse, which I then send through a pulse generator. And if you don't know what this is, I'll
leave a link in the video description here. So I then take that output pulse from the pulse
generator to create a flash and take a high speed photo. Now why would I
want to do that you ask. Answer? Because it's awesome. I mean look at that.
But after a while it gets kind of strange taking experimental photos of yourself
with firearms all the time, so I invited some friends down to Alabama, that you
might recognise, to take photos with me. OK
OK I changed it, and we're gonna see the kick, instead of the muzzle
flash. I delayed my flash.

Alright you ready to kill the lights buzz? -Yessir. Alright, hold on.
Just , just so I know, what do you think you're gonna look like? -American hero.
Alright. Kill lights. Ready for the count?
-Ready. 5..4..3..

[gunshot] -Well?
Let's see. -From my end that looked good. [laugh]
Yep it looked real good over here. -No I'm serious. It was like it was a flash of
like, American pride. Let's put this on your website.
-They're gonna sell posters of this. -Oh my goodness.
-Oh.. oh.. That's not what I was expecting. [laugh]
-You afraid of the dark? I'm goin with your camera dude.
-There's like two of you. You're like you're ah
-What's going on there? -You can put it on your website. That's all that matters man.
-That camera's broke dude. You should take that into the shop. OK now we're gonna do the
same thing, only instead of a revolver or pistol, we're gonna use a
.50 cal? -.50 caliber Yep. So this is Michael from V sauce and this is a
Safety Harbor .50 cal. It's not the Beowulf round it's the BMG round
so we've got a AR-15 lower, Safety Harbor upper and a whole lot of
awesome. Arm? -Armed. Alright.
3..2..1.. [gunshot]
-Did you see the flash go? Flash went. -Nice.
Nice. So uh
That's a little bit of muzzle flash. I mean, it's not like an amazing amount.
You know I mean, that's probably less than you're used to. -We could do better
I think we could do better. -Well look at that. Look what the flash did. It made that smoke cloud
more opaque. On the bottom right of the quantum composer, hit the blue button
-Blinking. Alright. Come back over here and I'll put the
round in the barrel. -Ready? Yep. -Alright.
-and 3..2..1.. [gunshot]
Awesome. -Wow.
This is kind of like a man test, if you can do this with your eyes open. -Look how
open your eyes are. Well yeah, I mean come on. [laughs]
So there's a handful of you out there thinking well why don't you just take the output from the piezo
and run it through a MOS FET or something like that. You can vary the threshold on
that MOS FET and then send a trigger to your flash. Why don't you do that Destin? Answer,
because I like taking pictures of the bullet itself. That's why. This thing has a really really
fine temporal resolution. It's like 25 picoseconds. So another thing you might
deal with is bullet blur. Bullet blur is calculated by the velocity of the bullet as it exits
the weapon, multiplied times the the flash duration. Now there's two ways to
decrease the bullet blur. The first way is a faster flash, and the second way is to
turn the weapon more acutely so that you're only dealing with the cosine of that bullet
velocity rather than the full bullet velocity. Now that's cool, but
there's something you have to do if you do that. You have to use a remote trigger, because
one of the major rules of gun safety is never be down-range of a weapon. So make sure
you do that. Use common sense any time you do experimentation like this. So there you are, now you're
trained on how to take really cool muzzle flash photos. Do not do this if you and
everyone around you is not heavily trained in weapons safety. Even if you are trained,
just keep in mind, accidents do happen so use common sense.
That is amazing, I didn't think we could do that. I did not think this would stop the bullet.
but it did -Get smarter every day y'all. Subscribe immediately.

[ Captions by Andrew Jackson ]
Captioning in different languages welcome. Please contact Destin if you can help.