It was a pleasure having Top Shot Dustin help us test out this movie myth. Be sure to go check out his channel. As always, the 1000th comment will receive a prize. Comment away and help us defeat the evil algorithm!
My dad was in the army engineers(Genie) he told me once they had to make a heli lz.Used detcord bit they got a ton of bandages from the ops docters and after wrapping the thick palms with detcord they wrapped them over tightly with bandages to direct the charge inward resulting in a perfect cut.Hope it helps
Come on you guys at “The Lab” muhahaha, your gonna have to try this variation of wrapping with bandages for clean cuts. You have a plausible story of its use, gotta find out!!!
@@MR-nl8xr truly... A license to make a house, license(s) to fix said house, license to grow food, license to sell that food, license to do manual labor, license to buy transportation, license to use transportation, license to be born! Everything in life requires licenses... Can't even exist without giving them a cut.
We will def do a follow up on most effective methods to clear trees. We don't have any heavy grain detcord right now, but we do have a ton of other party favors to get the job done. They heavy grain stuff is surprisingly not in stock right now.
The cord we used was definitely stronger than 50 gr. But we wrapped it 10 plus times in uniform, not over another wrap. For the bigger trees we also had 2x2 angle iron packed with C4 for a direct cut shape charge. We used what we found at hand a lot of times. We did a lot of sketchy sht off record.
Yes Det cord can be used to clear LZs Army Engineers use this to do so on small trees like that. There are calculations for exactly how many feet needed for tree diameter, they need to be tightly wrapped, and then a good couple of tight wraps of gun tape(green duct tape) really help.
I'd like to see the duct tape, water bag, angle iron and bandages all tested against each other. That would make a great video and fantastic comparision.
I know the army has a specific method for removing trees using det cord (my father was stationed in the Ivory Coast and mentioned the engineers using it to clear fallen trees). It would be interesting to see these guys explore the most efficient ways to destroy various objects
During my time in the Swedish forces I’ve seen it used very effectively on conifers and birch - but yeah, I suspect both the type of cord and the type of tree are significant factors in whether it works or not. And a buffer would definitely make it more effective, even if just a plastic bag of water wrapped around it.
On related matter i think that emulsion explosive should have been wrapped around the tree much as possible and not placed like that along the tree. This is to cut as much of the material keeping the tree upright.
While in Vietnam I was told our Detcord was C4 in a tube. Definitely a different type of explosive than you are using today. We also adjusted our hand held devices with a little added C4. We also made our own devices, like C4 packed into a potato chip can, set off with a concussion grenade. Just saying your results will be different than what was used in Vietnam.
P&W had a pit out back where they did explosive forming using detcord. The stuff was wrapped around a kirksite core then the sheet metal cylinder that was to become the afterburner liner dropped over it. A multi-piece mold then bolted around it and the pit then filled with water and a huge lid secured on top with heavy bolts all around. A vaccum was pulled then the cord detonated which pushed the cylinder out into the mold making a beautiful new AB liner. We had different recipes for each part with so many wraps of a specific weight cord and while the shots I witnessed went well....the guys doing it told me that back in the day someone transposed a decimal point and put 10x cord strength in that should have been...and blew the lid (which was like 30ft in diameter) off of the pit. Fun times using detcord!
In Afghanistan we used det cord all the time for LZs but never baby 50. I’ve even seen 7’ door charges. But on large trees we always would use C-4 and make little packs. I don’t recall ever using baby 50 by it’s self to take down trees. Normally it was for recovery and we had plenty of time for selecting & prepping the site. It wasn’t a qrf exfil. We usually went in an area for 24-72hrs and we would start preparing the extract as soon as we were on the ground. If we were not getting shot at. The areas in NE Afghanistan where you commonly had to take trees down the enemy was very committed to get you out of the valleys
It would be neat to see a controlled demolition of a substantial dead tree. Like shape charges to slice the branches and trunk into rounds, and before the pieces hit the ground a secondary detonation in the rounds splits the rounds into firewood sized pieces. The closer you can get to a pile of firewood where the tree was the better.
As a 12Bravo there is a formula to determine how much detcord to use based on tree diameter. It's been so long though I can't remember. You also need to "contain" the blast. Just like blasting rock, the hole just isn't filled with explosives. It is also backfilled with dirty/drilling shavings. You just let all the force/gases expand outward.
I've done a few shots of det cord to drop trees down at the demo range at Ft Knox back in early 90s and few other charges. C4, TNT, shaped charges and cratering charges. Shaped charges, C4 as a cutting charge and TNT do a better job dropping trees but the type of tree and moisture does make a difference.
From a military demolition manual, to shear trees you are supposed to wrap det cord in opposing directions to create a shear at the line where the opposing directions mean.
You have to remember that det cord like pyro fuse have a burn speed. This is defiantly not the stuff we used in Nam. It was white. And we'd put like ten wraps around each tree. We weren't worried about how much or the cost. Just get it done. I've also see the military use a 15k daisy cutter air gas bomb to clear an LZ.
during my time with german combat engeniers i got the training class for demolition-prepping. We were told how to cut trees with detcord. If i remember we had some cheat-charts with diffrent kinds of wood and thickness, and corressponding wraps of detcord needed, on them. Also the way how to wrap it was very importent. Afaik it was like a pyramid: if you need 10 wrappings than its 4 bottom layer, topped by 3 topped by 2 topped by 1, nicely done that it looks like a pyramid, and it all got ductape on top to keep tight and in place. the poles we cut down were clean cut (almost like with a shape charge)
I think part of the problem is that you need to wrap the trees like it comes off the spool. tight, even wraps. everything touching the tree. the way you had it, with bunched up randomness, the base layer is shielding the tree from all the blast energy above it.
Thanks for giving us all a chance to watch the kinds of things we've wanted to try since we were kids, but most of us will never get the opportunity to do ourselves.
In veitnam they used the good ol daisy cutter a 10k lb bomb with a roughly 10ft fuse on the nose and it would do a damn good job at clearing out landing pads in that thick jungle . Cool thing that happened my grandfather got awarded two medals from both the US and Vietnam for coordinating a drop of a daisy cutter and some other smaller ordnance from a 3 plane b52 formation on a group of N .vietnamese tanks that were attacking a base in or close to kontum . (Edited spelling)
Former USAF AMMO here. BLU82/B's weighed 15,000lbs with a net explosive weight of 12,600lbs. No need to engineer fins for them because they were going always designed to fit a cargo aircraft, so why design ordnance to get dragged out the back of a c130 only to have it drop off a sled...? That's unnecessary weight and engineering. The Massive Ordnance Penetrator needed them for guidance and to gain as much aerodynamic efficiency to increase its kinetic energy on impact, but these are dumb bombs that carried a flash tube, so the explosion propagated is energy above the ground & not into it. I've heard of Vietnam soldiers doing this, but they used about 1000 ft of det cord and they'd clear anything remaining with machetes. Although, that was secondhand information from a Navy Seal we used to store and deliver munitions to downrange, so take it with a pinch of salt.
Most people don't know that det-cord is fuse that burns really fast and therefore is considered an explosion but you guys know this. I used to be a powder monkey in a marble mine and we used slow-burning fuse to detonate our det-cord. I had to cut a small piece and time it so I can know how much to cut in order to get out of the mine before it blew. I believe that was my all-time favorite job. Thanks for the demonstration guys and y'all have a great day and stay safe and keep your powder dry!
I was in an antiartillery unit in Vietnam, I saw how this works first hand, not in a movie. The engineers did not give us any warning before they started clearing trees, I am not sure what size cord they were using but those trees came down fast and we were ducking from the pieces flying. When the dust cleared we had a clear field of fire for the 155s.
As a retired Sapper in the Canadian Army I appreciate your channel. I miss blowing stuff up. Have you given any thought to doing an episode on improvised .bangalore torpedoes?
I love seeing two great channels im subbed two collaborate ! I cant wait to see more in the future ! great video ordinance lab :D Love you Topshot Dustin
I'd be interested to see a video giving a breakdown of the cost of different types of explosive. I constantly hear of how some types of explosive are cheaper or more expensive than others, but just how cheap/expensive are they? A quick cost analysis on blasting caps/det cord would be interesting to see, too.
I would love that. They should put the cost of each explosive in at the bottom corner or something. Would be cool to know the value of everything they splode'
That would make a good episode, especially with a "bang for your buck" element of comparison. Maybe compound X is less powerful than compound Y. But then if compound X is pennies per truckload and compound Y is worth its weight in gold, you'll use X whenever it can do the job.
@@johnladuke6475 that would make an interesting episode but they'd need to go further into explaining the different qualities of an explosion: Brisance - how much an explosive would cause a shattering effect... Heat & Pressure - they usually go hand in hand, but if you watched the thermbaric episode, you can see sometimes the heat of an explosive can lead to a slower shock wave carrying higher pressure. This causes different damage effects than something with higher Detonation Velocity - the speed at which the reaction expands from itself, all vary from explosive to explosive. Perfect example : when they attempted to blow up a washed up whale on the beach in Oregon(?) back in the 70s, they really didn't use the right explosive for the job. Instead of using TNT, they should have used something with a much faster detonation velocity like RDX or the slightly faster HMX. This could make an excellent precursor "use the right explosive for the job" to a "best bang for your buck" episode.
Just started the vid an before I finish i will say as a retired Army 12b Combat Engineer we did train on how to use only det cord to take down trees. It works rather well and can be set up relatively quickly with a good squad
MY unit in vietnam used the det-cord jumped fron claymore to claymore mines as many as 10 and when the charging handle was squazed all mines would blow at once, worked good with enemy comming into wire. 4th inf. div. 10th armor The highlands vietnam. 1969
I see many people already commenting the same. I was a 12B Combat engineer. Our old timers including my fathering have certainly cleared trees using det cord. larger trees, more wraps or add C4. P=Plenty. I'd definitely like to see this done again with the right materials and correct methods.
I was sure that would work!! My dad was the blaster at our local quarry for bethlehem steel. He told us that they would use detcord to cut 50 gallon drums in half. I will have to ask him the size cord they used. I suspect 50, as they usually used it to tie charges together from hole to hole and that would have been plenty. Very enjoyabe as usual!!! Thank you!!
When we were in the Americas we were shown how you use it in conjunction with shapes of metal to do enormous amounts of damage, especially structure like bridges. It's interesting to see how benign you make it out to be.
Had to do this at green beach, Subic Navel base in the late 80s. We found out, like you did that you have to use a pyramidal wrap that creates a shaped cutting charge. You have to go pretty heavy with the thicker stuff . Also got to re open a lagoon after Pinitubo erupted using nothing but 1500' of det cord and a 40 lb cratering charge. Bounced the blast off the bed rock and the det cord pushed the ash & water out of the lagoon. We ate pretty good that night on the fish that were blown ashore.
I know in matterhorn and some of the other books I've read written by Vietnam vets they often talk of using c4 and not tnt but some other type of explosive for tree clearance and for building bunkers, I don't know for certain what the others were or if there even were alternatives in general issue I am sure that c4 was mentioned early and often. really cool vids and very cool channel, thanks for taking the time and effort to bring us good stuff.
I took down a tree on a munitions range way back. Couldn't tell you the type but it had about 100-125 ft on it. Ah the days as an AMMO troop. Great vid. Munitions busters lol
Dome this in my Army(Germany) time. The diameter of the tree is important to the wraps. Bigger trees, we used TNT and sandbags, to orientate the blast. Sometimes we used a drillhole for big trees. It‘s all math and pysiks
I'd like to know what (relative) grain detcord the boys in 'nam were using, i know they did pad/ buffer to an extent for shaping/ directing the blast but i'm curious to what strength theirs was. Very cool stuff!
one of my friends was a door gunner in a helicopter in Vietnam. he told me his job was to "clear hot landing zones" for his helicopter to land in, and almost everyone he worked with in that job was shot, with a lot of them dying. my friend often said he only survived because he was shot in the hand and it destroyed his ability to control the machine gun he used, and they forced him to medically retire. i never really understood what he meant by "clearing a landing zone," and i never asked for details because of the look on his face when anyone asked about it.
They often use detcord to weaken the tree then use the tank ran over. It has specific benefit for tank ambush tactic. Quick and reliable. If the military really want to clear out the whole area, they would use stick shape charge which has more effect, not just cut down the tree, they also use to clear out the fence and land mine. My friend's father was a Major General of 7th Infantry Division of Vietnam military locate in the South. I remember we often follow his father to the exercise field. They often send a small group go ahead to setup the detcord or the shape charge stick depend on the tactic. But like i said, the detcord just use to weaken the tree but still keep the tree stand up. This tactic work really good for tropical environment. It will allow the tank to get through a thick jungle in minutes. But the one they use has a square shape not round, they also has the triangle which a bit larger, both can cut through 5mm steel.
When I was Up North in a mining camp we cut down 10 trees with det-cord the trick to it is you have to de-bark around where you put the cord. If you don't the bark absorbs the shock. Now it might have worked only because it was so cold, -40 Fahrenheit. I don't know what strength the cord was, but it cut those trees like butter. They were all 6 to 8 inches in diameter.
The Myth is busted! I like how you guys or people in general do real life tests to prove movies wrong. Apparently a lot of movie producers had no idea how real life realworld really works.
Me hearing about felling trees with detcord: I don't think it would work without a lot of detcord. Me seeing them wrapping quite a lot of detcord around thin trees: Maybe... Me seeing the result: looks like trees are more resilient than I thought. Me hearing explanation: now I want to see those higher yield detcords being used against those trees!
The most important question is "how long did it take you to wrap all that cord? You could have cut all those little trees down in no time at all, with a good chain saw! You also forgot that when the trees are down, they are still in the way. It really is a job for a chain saw!
we used det cord as initiators for shaped charges, I would like to add the vegetation is much different in the tropic than it would be in in the American South and desert scrub, you need to revisit this with Demo experts
Ooh... and another thought, on the entry have some "wavy" cord up against the trunk.... what I mean by that is cord that's led up and down so it presents several short lengths of cord along the grain, instead of across it, and having that cord initiate first. You'll lose some shock from the outer cord coming up against the pressure of the inner cord, but when it does hit the wood it should already be splitting open with the grain and compromised.
Idea Shaped charge cannon, instead of launching a projectile it shoots a jet of liquid copper. Would have to be tremendously over built to survive firing.
Wooden or steel collars would've definitely seen a number of those trees lying down after the charge was directed inwards. Time for more experiments to certify which materials would or wouldn't work.
Do we know what grain det-cord they may have carried with them for a mission like that one as depicted in Vietnam? I believe the bombs they dropped to clear an LZ in Vietnam's jungles were known as Daisy Cutters and/or Wad Cutters, and I think they had a detonation trigger that extended beyond the nose of the bomb by several feet ( 6-8 feet?) so detonation would occur just above ground - almost at grade (due to the rate of gravitational acceleration of the primary explosive). I presume they minimizing cratering since landing a helicopter in a dirt bowl probably brings it's own issues. They must have been fairly effective in clearing away not only thick brush, but any forestation of hardwoods or bamboos growing in the LZ. I'm trying to picture the blast front's compression wave movement that would result from the above-ground detonation and wondering how you might able to simulate tha effect t using just a heavier grain det-cord, It was an interesting test and demo. Thanks.
Daisy cutter bombs were 15000 lb FAE usually dropped from a C130 Hercules aircraft. It was known as the BLU-82. In the movie Outbreak they use one at the beginning of the movie.
0351 anti-tank & demolitions here. Det cord actually does not explode. It, however burns at an incredible rate. For instance, if you laid out a line from New York to Los Angeles, it would take around nine minutes to burn
Crazy, and I thought that was way too much cord! Video suggestion: How much Det Cord do you ACTUALLY need to clear a landig zone of small trees 😈 I know it's unrealistic because of the amount needed... but still, the imagined picture would look so nice.
as a british army royal engineer detcord can be used to clear an LZ. it have to be wrapped in a pyramid form and 1 layer of det cord per inch diameter of tree . thats hos detcord is used to cut down trees
Detcord CAN be used to clear trees, however, the rule of thumb is that you need 1 wrap more than the number of inches of tree diameter. So for a 12” diameter tree you would need 13 wraps of cord, and it must be wrapped in a pyramid shape, getting smaller with every wrap. I’ve personally never done it, but this was what I was taught in EOD training. Also, you probably should’ve done each tree wrapped individually and taped a priming loop on each one, then tied them all together after the fact with more detcord, obviously maintaining wave propagation directionality on the tie in.
We experimented (played) with using red military der cord to clear trees on an Airforce bombing range. We dropped hard wood trees up about 6” diameter no problems. Don’t recall how many wraps, but it wasn’t that many. Stump would end up very splintered. Don’t what the rating the cord was. Good fun.
can you do the same with cool linear shaped charges ? like the small demo cutting charges used by the armyto clear barbed wire and breech barricaded bunkers, demolish bridges etc - the ones light enough to be carried in a rucksack by the demo guy - like 30 mm rails
You must wrap diagonally so you get a shear.... and helps to cut in and or place packing on the outside of the det cord... causing the blast to go in.... like to see you do a flat of cement with dynamite or what ever laid on top then the same with a sheet of paper placed over the charge then sand bag on top..... the saying is a stick of dynamite on cement wil just brush away all dirt but if you place a sheet of paper over that charge the charge will be directed down causing considerable damage..... never got to see this for real was told this in eod training many years ago
You guys should do a myth busters type segment for explosives! You could pull in a bunch of money to help grow as well as show everyone how stupid Hollywood movies really are.
The two best ways to take down trees are to plant the charge under the tree, (directions found in old copies of the Dupont Blaster's Handbook) or by drilling the tree and placing the charge inside. (this uses far less explosives). Lastly, linear shaped charge works well on small diameter trees. (hard to come by and expensive. Also if you are going to plant the charge under the tree. have someone build you an Ashley Core Punch. It's a pretty simple tool to build, directions also found in old copies of the Blaster's Handbook. Fun video to watch but the outcome was no surprise.
