Articles , Blog December 5, 2019 100 Comments AK-47 Underwater at 27,450 frames per second (Part 2) – Smarter Every Day 97 Dereck Turner Post navigation Rolled Paper ProjectsDIY photo frame/How to make photo frame at home/Very easy and fast/Last minute gift ideas 100 thoughts on “AK-47 Underwater at 27,450 frames per second (Part 2) – Smarter Every Day 97” Waugy 370z says: July 7, 2019 at 11:11 pm That collapse and pulse of the bubble is pretty cool looking. Reply ciaostrada says: July 8, 2019 at 4:20 am i would add to your good insight another phenomenon here and propose an explanation. Perhaps both my observation and explanation are incorrect. However, it seems that the glass bubble collapses before the fuzzy bubble (perhaps in spite that the latter had more time for expansion and collapse). The glass bubble should be mostly vacuum – caused by the bullet edges breaking through the surface tension and pushing the liquid water out and forming a void. By thermodynamics, indeed there should be vapor inside, but I posit that there is insufficient time to come to vapor-liquid equilibrium. The fuzzy bubble, on the other hand, was created by water vapor from in front of the bullet, not behind it, and it is more in tune with vapor liquid equilibria. Therefore, the glass bubble has less vapor and thus less internal pressure than the fuzzy bubble. The external pressure (liquid) is roughly the same on both bubbles, and assuming that the both bubbles are roughly similar in area, the overall collapsing force is higher on the glass bubble and it will collapse before the fuzzy bubble, which it does. Reply The Pied Piper of Appalachia says: July 9, 2019 at 10:49 pm Bible verse at the end ruined the vid…. Reply Anthony Trupia says: July 10, 2019 at 9:57 pm Has anybody seen the episode of Mythbusters when they a shot the 50 caliber in the pool and the bullet didn't go no more than 5 feet in the water Reply mazin alharthy says: July 11, 2019 at 9:59 am Can you please try it in the dark and see if there is illumination from the bobble? Reply Shannon Neely says: July 11, 2019 at 4:37 pm Really cool video with great explanations thank you! Great job! Would love to see this same test done in the dark or very low light conditions. Might help solve the question of flash? Reply kevin Roberts says: July 11, 2019 at 7:30 pm Front surface mirrors. Reply Jon Cocks says: July 12, 2019 at 5:58 pm I bet you went full auto off camera.Love the channel🇬🇧 Reply onehit pick says: July 14, 2019 at 6:04 am The multiple cavitation echos after the firing is a really great capture. Reply kathy taylor says: July 14, 2019 at 2:48 pm If you were to tape off the end of the barrel and chamber a round first before submerging the AK then their would not be any water in the barrel for the built to push out so the bullet would me traveling faster and would go a bit father and make a bigger blast cloud at the end of the barrel. A fun video Thanks Reply Johnny says: July 14, 2019 at 10:36 pm How far does the bullet travel? Looks like after just some 50cm, the bullet would be so slow it can't puncture paper. Reply Prashant Mohan says: July 15, 2019 at 3:29 pm I'm sorry but I couldn't comprehend all this with my inferior brain I was just here coz of the slo mo guys. Reply Ace of Spades says: July 17, 2019 at 1:10 am Just me that can't find part 3? Reply Cade Perkins says: July 18, 2019 at 3:47 am At the point of implosion when there is a flash of light (and Destin considers sonar luminescence), notice that the image of the muzzle (and the rest of the frame for that matter) jostles back and forth. I would guess that about the same time it takes for the first bubble implosion is when the most energetic wave reaches the mirror box. It would be no coincidence that the bubble oscillation would then be in phase with the waves reaching the mirror. So Destin is likely correct that it is not sonar luminescence and likely a "reflection of the sunlight", but more specifically the change in apparent brightness is due to variation in angle of combined refraction/reflection through the mirror box. If the camera were moved or the box manually vibrated, one might also see a change in the apparent brightness of the overall image. The effect is just more pronounced when it occurs in sync with the bubbles. Reply Cade Perkins says: July 18, 2019 at 4:18 am Also, remember that pressure is very much directional. It is simply an average force over an area… and the force in a liquid or gas can be directed so that more of the average motion of the particles are in a certain direction and hence the average force exerted is also higher in that direction. In static equilibrium, pressure is essentially equal in all directions over a small surface area at the same depth. But while flowing the pressure is generally only lower at the boundaries orthogonal to the flow. The pressure is actually higher along and in the direction of the flow than against the boundaries of the flow (i.e. tube walls). If the pressure were also lower in the direction of the flow, it would be lower than the water outside the barrel and so it would not escape the barrel, rather it would be pushed back further inside the barrel by the higher-pressure water outside! But that's not what happens. I mention this because like so many other subtle–but often repeated–incomplete ideas in science can spread misconception later on. Reply 周慧 says: July 18, 2019 at 12:58 pm It is awesome ! I like it ! Reply MagnificentZGamer says: July 18, 2019 at 9:22 pm 4:33 here is rare photage of Trump's AK-47 making a black hole Reply Chernov Gaming says: July 18, 2019 at 10:04 pm 2:16 What’s with the left hand. Just hold it normally. Reply Kelly Wilkinson says: July 20, 2019 at 6:58 am between 2:02 and 2:16 Wooahhh did you see the shockwave rippling toward the camera; and how the rifle wobbles up and down like a piece of rubber?Wowww it's so cool how around 4:45–4:50 the air which was initially pushed radially from the the bullet then is pulled into the channel created by the bullet through the water.Thanks for explaining the Rayliegh-Plesset equation. Reply chip599XX says: July 20, 2019 at 11:18 pm VGR Triad and VGR GSF are teaching to shoot a AK-47 in Underwater Reply Joshua Wilson says: July 21, 2019 at 11:56 pm Hey Destin, I have a quick question for you. Well maybe two, the first is, is there a way to message you on YouTube without messaging in a random video? And the second, and real question, is do the sounds that come from your throat sound different than the sounds that come out of your mouth? I was listening to an audiobook, and it mentioned a sticker that goes inside of your mouth that acts as a communication device. It's a fictional book and it's like a future technology that's been made up and I was curious if the sound that came from your throat into your mouth would sound the same as the sounds that come out of your mouth when you talk. I didn't know if the sounds were generated by your vocal cords and your lips and jaw inside of your mouth the same as they sound when they come out. Reply Richard says: July 22, 2019 at 1:02 am Fantastic video as always. The bullet exiting the muzzle resembles a bullet impact into ballistic gelatin. My question is, what is in the temporary cavity? I understand that the water is pushed apart as in the ballistic gel, but where does the (what looks like) air come from? Soon after the temporary cavity is created, it collapses/implodes in on itself, but no air rises to the surface. What is in the temporary cavity? Thanks Reply Sharkbyte1000 says: July 22, 2019 at 6:47 pm does about the same thing happen if you shoot 2 feet above water into water? does the water slow it down so that it only travels about 4 feet in the water? Reply Bret Bacon says: July 24, 2019 at 10:18 pm I just got stupider duh hatethis channel troll Reply BadHombre says: July 27, 2019 at 12:16 am Exactly how my farts look, except for bigger bubbles. Reply DisGuyBeGaming says: July 29, 2019 at 9:17 am Unless your from Alabama AYYYYYYY Reply Bubblezov Love says: July 30, 2019 at 9:31 am I'd quite like to see those beautiful collapsing bubbles happen through a column of dyes or inks in the water.. Destin. get the wet suit! Reply life of slav says: July 31, 2019 at 8:27 pm I want this ak Reply vanhelvn games says: August 1, 2019 at 4:41 am Ô chú làm hay lắm việt nam vietnam Reply Justin Newman says: August 2, 2019 at 1:50 am The bullet does not start tumbling until it exits the cavitation that preceded it Reply Hmpppf says: August 3, 2019 at 7:48 am Your AK is ugly with it's plastic furniture, upgrade to cool communist wood. Ohh and death to communism. Reply Salty_Mex27 says: August 3, 2019 at 5:43 pm Unless you are from alabama😂 Reply Mockturtlesoup1 says: August 4, 2019 at 6:08 pm it would be interesting to see this repeated in a pitch black environment to determine whether it is truly sonoluminescence, or just reflected light like you hypothesized.that has been an ongoing debate on so many ballistics gel videos I've watched. Reply Steve Wheeler says: August 5, 2019 at 2:07 am In your footage and the slowmo guys, I noticed something. The snub nose revolver projectile seem to travel straighter and didn't tumble as much. Is this possibly due to the shorter barrel not housing as much water volume, in turn lowering the hydraulic affect? Which would allow the bullet to gather more spin and less pressure to have to push thru? Reply alsmith20000 says: August 8, 2019 at 8:22 pm Would you consider firing more than one shot in as automatic fire in this context?I'm thinking about the effect of the compound shock waves, but also if the second round is traveling in the cavity left by the first, the round may travel further and more elegantly. Reply Ammad Ali says: August 9, 2019 at 7:38 pm we have to shoot slow mo….. lets call slow mo guys! Reply Desmond Penrose says: August 10, 2019 at 2:06 pm Following the recent shootings in the US don’t you feel you should stop glorifying guns of any kind as a nation you can’t cope wither the responsibility Reply Hope Edwards says: August 13, 2019 at 5:30 am This is why I love YouTube. Great video man. You won me over with this video and now just made me a subscriber. Reply Elite Engineer says: August 13, 2019 at 8:13 pm Did he said sweet home Alabama Reply Invictus Sin says: August 19, 2019 at 11:30 am Can't find part 3 Reply Nikhil VJ says: August 19, 2019 at 1:14 pm You made this before the era of SJWs getting triggered over anything related to guns. Kudos! Reply † Wilhelm Liebehenschel † says: August 20, 2019 at 1:32 pm i need video shoot RPG 7 in water Reply Canadian Airsoft says: August 20, 2019 at 10:19 pm Lol you got the slo mo guys Reply Bolu2392 says: August 21, 2019 at 2:49 am I appreciate the demonstrated verbal communication for gun safety in this video. Reply Qhajajs Shsks says: August 21, 2019 at 4:35 am Lol, that is not an ak47 🤦🏼♂️ Reply FPL Finesse says: August 21, 2019 at 8:00 am Is it possible to fire a gun fast enough to get bullets to travel through the cavitation bubble of the previous bullet and would this then make the bullet travel further? I know this is 6 years old but I think you should do it again but mount the gun and go full auto Reply Carl Basky says: August 23, 2019 at 8:02 pm I didn't kniw destin are friends with Jake Gyllenhaal and Brian Quinn? Reply MotoCzar says: August 25, 2019 at 6:42 pm Sitting a $200,000 camera beside a pool….. ballsy move Reply gk10002000 says: August 27, 2019 at 4:45 pm still my favorite myth busters show where they fired various guns into water. Amazing how NOT far the bullets went. Unlike all the old hollywood movies that showed bullets streaking down past the heroes. Even the 50 caliber disintegrated Reply gk10002000 says: August 27, 2019 at 4:48 pm so much force on the front of the bullet. Not hard to now see why the bullet quickly turns off center instead of pointing straight ahead. Then once the bullet gets not pointed straight in the direction of the velocity vector, side forces are huge and the bullet can't go much further or disintegrates into pieces Reply Marcellus says: August 27, 2019 at 6:08 pm can you shoot a gun in an enclosed water filled container? would it just burst? and what would happen in the inside?Since Water cant be compressed, how would an explosion look like? Reply yogendra singh says: August 30, 2019 at 2:56 pm Awesome vedio Reply Russelheim says: August 31, 2019 at 9:53 pm I know it's hard to see, and I hate to be that guy, but, that isn't an AK-47. It's a 74. Reply Chris Hernandez says: September 1, 2019 at 10:15 am 6:30 There's no pressure in a cavitation with no gases or air in it. Some of the "bubbles" from a gunshot are cartridge exhaust bubbles, some are cavitations with no gas inside, especially surrounding the projectile. There was a video somewhere about a fluid in a glass vacuum tube, and the fluid would slam against the glass almost like a solid because there was no resistance or gas in the way. Reply gkarjala says: September 4, 2019 at 2:52 pm Mad respect for anyone who has cajones to do this. Reply riuphane says: September 6, 2019 at 3:30 pm I just love seeing slo mo guys collabs Reply Lars Murdoch Kalsta says: September 7, 2019 at 9:42 pm You see sonoluminescence in ballistics gel a lot so I can't imagine why it wouldn't happen here Reply oudskii says: September 9, 2019 at 9:30 am I would have never seen this in my life Reply fun with jiyad says: September 10, 2019 at 7:36 am This is called akm Chinese ak47 you should have to test on Russian ak47 Reply miggy rob says: September 11, 2019 at 2:20 pm I just learned that ak rounds tumble like a tornado. Reply Zero Two says: September 12, 2019 at 12:03 pm I really want the camera to play CS GO Reply Dimitar Donev says: September 15, 2019 at 6:03 am I don't think the gas from the piston cycles the weapon – it is just enough to unlock the bolt. The pressure inside the barrel is what does the main job. The same pressure that pushes the bullet forwards is what pushes now the empty shell from the cartridge and the bolt backwards. If the bolt is not locked the bolt would go back way to soon and a lot of the gasses and the energy will simply be lost. The reason we have those gas operated rifles is so we give maximum inertia to the bullet possible but not wait to much because if the bolt is unlocked too late then the gases will escape the barrel after the bullet has come out and there won't be any pressure left to cycle the bolt. That's why the position of the small hole on the barrel that takes small part of the gas pressure to unlock the bolt is so important – too close to the end of the barrel – you risk experiencing a jam, too close to the entrance – the bolt will unlock and the pressure will escape way too soon before the bullet gets is maximum speed. Reply Safton says: September 17, 2019 at 3:32 am Lethal Weapon 4 brought me here. Reply Ibnu Syahrani says: September 20, 2019 at 2:44 am Wow , thanks to add subtitle bahasa Reply Robert Garland says: September 20, 2019 at 7:02 am I am curious as to what the effect would be if you were to plug the end of the barrel so it would not fill with water, perhaps you’d get different results? Reply marty mcfly says: September 23, 2019 at 2:31 am I’m not trying to be controversial when I say this, but with all your knowledge, how do you convince yourself that that there is an almighty creator? Again I’m not trying to start a beef, I as an atheist am honestly curious. It’s just that all research I’ve done proves evolution to be true! I would love to believe in an all knowing, all loving, perfect God, but I can’t based on what I know. Reply Marcus says: September 25, 2019 at 8:16 pm The big bang Reply Vladimir Harkonnen says: September 26, 2019 at 6:25 pm We should ban this gun, and ban this video. Reply Ben Clark says: September 27, 2019 at 6:23 pm Something akin to laminar flow following the bullet there? Very glassy and smooth… Reply A Bit Of A Pickel says: September 28, 2019 at 1:57 pm I understand this is science, but I LOVE my ak. That's really cool what you did, and I think people should at least try firearms out for them seleves SAFLEY. Reply Nozome_ Ushiro says: October 2, 2019 at 2:03 am Vim pelo vídeo do BaroneLab Reply feelthepayne88 says: October 3, 2019 at 2:07 pm You guys should colab more often. Reply Beqa shekiladze says: October 7, 2019 at 9:28 am Hey, why the bullet is tumbling while it's being shot. I observed the same in Slo Mo Guys video, but the pistol did tumbling, not revolver. Reply Zanou says: October 8, 2019 at 7:56 pm 0:50 wow that was gav from slomoguys Reply Douglas Radzanowski says: October 10, 2019 at 7:57 pm so, that bow shock glassy appearance, is that almost like the inverse of laminar flow? Reply Soulaimane El Flihi says: October 10, 2019 at 9:26 pm The question is how can that makes me smart ?? Reply Minecraft Is still good says: October 12, 2019 at 7:27 am You should try this with only the tip of the gun in the water lmao it will just explode Reply it's gaming time says: October 13, 2019 at 5:50 pm At 5:44 to 6:00 the bullet skip above the water Reply it's gaming time says: October 13, 2019 at 5:54 pm I mean 5:44 to 5:56 the bullet skipped above the water Reply Brian wroblewski says: October 16, 2019 at 11:11 pm Dustin, I’d like to ask you an aeronautical question as it relates to fluid dynamics. Reply Crusifix Jesus says: October 17, 2019 at 8:57 pm the camera is only worth $9863572580683-63406753684 let's put it by the water Reply josh smith says: October 18, 2019 at 4:15 pm Did the Ak cycle ? Reply monksally says: October 20, 2019 at 10:37 pm Remember that time Mel Gibson killed Jet Li with an AK-47 underwater? Good times. Reply Jason Adkins says: October 26, 2019 at 12:07 am I am curious about the sound it makes under water. Reply Wesley Beans says: October 30, 2019 at 3:14 pm what happened to part 3? i cannot find the video after this one. Reply Ana Ortiz says: October 31, 2019 at 8:55 pm happy Russin noises Reply deku_ trochee says: November 2, 2019 at 3:24 pm Slow mo guys fans me from the first😆😆😆😆 Reply ikram khan ikky says: November 3, 2019 at 4:35 am Amazing, well exposing Reply Srikar Kandikonda says: November 6, 2019 at 7:38 am Mom, the neighbors are playing with guns in the pool again! Reply trialnterror says: November 9, 2019 at 12:29 pm I tried to find your video about Russian frog man gun…… can’t find it! Arrggggg Reply Richard says: November 10, 2019 at 11:43 pm Heres a idea try putting the bullet back in the cartage I will bet it not a tight fit because……? Reply Cyber Gaming says: November 11, 2019 at 6:41 am in our country,the fire gun very illegal… Reply Mr Putman says: November 14, 2019 at 9:25 pm Friction! Cooks the water around it, in the same way a submarine or prop in water creates cavitation, freakin awesome vid!!! Imagine trying to make that cavitation silent for submarines…:) Reply Corey Steed says: November 15, 2019 at 3:24 am Very epic Reply RoadKillzine says: November 15, 2019 at 9:21 pm Americans their fing guns… sooo boring Reply PyroJasonExplodes says: November 20, 2019 at 9:42 am How about that recoil control? Reply Polack Wizerd says: November 23, 2019 at 7:11 am You realize how close you are to committing a felony here?? Any rifle under 26 inches must be registered by the ATF and you need a special tax stamp.. Reply Buckwild Screening says: November 25, 2019 at 8:12 am What if aks weren’t waterproof Reply Pale Zombie says: November 30, 2019 at 7:15 am I’m shocked some people from Alabama that have five working brain cells. That’s incredible! Reply Myungkyun Yi says: December 2, 2019 at 7:09 pm No guns. No wars Reply Leave a Reply Cancel reply Your email address will not be published. Required fields are marked *Comment Name * Email * Save my name, email, and website in this browser for the next time I comment.