4:53 The way the steel of the barrel sheared is absolutely *terrifying* - because it's sheared, not burst open. The steel didn't even have the time to BEND.
Well I think we can safely say that the SLAP round that Scott fired was definitively not C4 spiked. The damage was totally diferent in appearance. I know its expensive but could you blow the next one up with pistol powder and analyze the results?? Also It would be better if done in a contained area so its easier to retrieve the parts for said analysis. A lined 20' shipping container perhaps. Many thanks for this Mark. I really appreciate your diligence in solving the SLAP mystery. On top of that you are getting some nice high speed physics footage in the process. Give the SloMo guys a call and see if you could get a collab going. I'm pretty sure they would be interested in the solve the SLAP mystery too. I know I would if I had the tools! Take care stay safe. Jimbo.
C4 was never even an option. C4 is only detonated with a blasting cap at like 50,000 fps shock wave. The pressure inside the rifle isn't even enough to detonate C4.
The detonation velocity of around 26,000 feet per second makes steel react like putty; the coolest thing is how the breech was gone so fast that the bullet barely moved. If you run another experiment you should invite Edwin over so he can pick up all the hot pieces.
This reminds me of the "cap confinement tests" we would perform on potential explosives (safety testing in a chem lab). Basically, a five to seven gram sample (depending on density) would be (very carefully) tamped into a bore in an aluminum round and topped off with a blasting cap. The resulting mini pipe bomb would be wired up and buried in a one cubic yard sand box (made from railroad ties) and then popped. High explosives (detonants) would shatter the aluminum round into sand sized particles, while low explosives (deflagrants) would deform and tear it, like an over-inflated balloon.
This is helping me more and more dismiss the idea of a sabotaged round in Scott’s accident and be more and more comfortable with it being a hot load using pistol powder. Thank you Mark for your tireless work.
The sabotaged round theory never really made sense, unless it was a deliberate attack on Scott, which there's zero evidence for. The idea that there would only be a single sabotaged round in circulation in the US that Scott happened to get seems highly unlikely. More likely, there would have been multiple rounds in circulation, with multiple explosions resulting.
C4 really could be dough. In Swedish, plastic explosives are called _"sprängdeg"_ which would translate as _"explosive dough"_ or outright _"blowdough"_
You flirted around it in the last video, but nerding out about matching the velocity of detonation of an explosive to the job at hand was one of my favorite parts of blasting. Needless to say, the velocity of detonation of any explosive or blasting agent is too high for a rifle. 🤣 Super interesting videos, and you do a great job narrating and talking. Thanks Mark!
I have seen explosions/detonations of other guns with rear pieces can going upwards and a little bit forward. If the material initially breaks at the bottom/ventral surface but is still attached momentarily for a millionth of a second the piece can swing in an arc from where it is still attached and as the last part of material lets go end going into the air and actually end up of forward of the gun.
@@loquat44-40 It does appear on the video that the cap separated at the bottom first, allowing it to do just just that. It's amazing how the ears stayed intact though.
@@freeman2399 Yep! That's why I figure the Cap is somewhere Forward of the explosion. I once saw a .45 Colt revolver blow out the cylinder from a significant 'Undercharge' the light target load had the powder in two piles within the case at the moment of ignition. The two 'piles' started two flamefronts that collided in the middle of the case causing it to blow. BTW, That's why detonation in a car engine with cheap gas will tear an engine up so badly! Nice video and cool explosion! You must have inserted a 'Fuse ignition blasting cap' into the case to be lit by the primer. Pretty Cool! Ya'll Take Care and be safe, JohnDF
In the last high speed clip, you can kind of track the cap... the trouble with high explosives is the pressure curve is so sharp you'll damage things before the pressure reaches something intended, and if you wanted to test the ears that kind of happened here. The entire receiver flexed as the cap and threads cracked off the barrel and it flowered, and you can see the cap tilt to about 60 degrees before being obscured, but... then you can see a fireball exiting the view at about a 30 degree angle, that's probably the cap shrouding some hot gasses and side products. I'd bet it made it one or two hundred yards, but it's intact out there somewhere...
Nothing more fun than C-4. It is amazing just how powerful such a small amount of explosives can be. Stay safe Mark, we are hunkering down for the blow. At least I won't have to water my grass for a few days. Semper Fi.
Mark would be wise to keep such details out of the public. This was an extreme boundary test. Next would be a case full of N310 to match the accident results. There have been many tests proving a true detonation in a firearm is nearly impossible. Over pressure events are common. Been there, twice. The case fails, the ensuing jet of 50,000 PSI gas at over 6000°F vaporizes brass, coating surrounding cool metal with a golden vapor deposit. Loss of case structure overloads bolt features and causes expansive deformation until pressure subsides. Even the mild .22 long rifle does significant damage on case failure. It shatters magazines, opens bolt faces and shucks extractors.
If you want to make it go boom reliably, just put a layer of primary (silver acetylide, PbN6, fulminate, whatever) between primer and C4. Most primer mixtures seem to contain lead styphnate, question is whether it detonates or just burns extremely fast upon primer strike. Detonation likely would provide enough pressure to detonate C4, whereas fast burning stuff does not. Primary detonates no matter what, setting off the C4.
I'd be using something like lead azide on top of the primer. The primer wouldn't be enough to detonate the c4, you definitely need a strong primary explosive.
It looks like the breach cap is in multiple peaces because the initial blast looked like it came out the Firing pin assembly in the cap button I would not be looking for a complete cap also it looks like the chamber parted in the centre you could see a lovley chunk of it making its way through the smoke thankyou for the video
Now, Mystic Meg's daily stars a few days ago, did tell me not to say "I told you so." But let's just say that it was predicted in the comments section of a previous video that a cartridge filled with an actual high explosive (as in a "spiked" round), rather than a pistol powder, would cause the gun to disintegrate around the breech into splinters of metal rather than component parts. Don't waste too much time looking for the breech cap: it is probably an ex breech cap, it has ceased to be. High explosives do a different _kind_ of damage. I doubt that you could use small amounts of high explosive to propel bullets at high speeds: even if the barrel was inches thick, the inner bore would shatter even if the outside diameter was so wide it didn't even bulge. PS: If cast HMX had been employed instead of C4, you'd be looking at smaller splinters. PPS: The suspect pistol powder is Vihtavuori N310. What if the other cartridges, which were hot but did not blow up the Kentucky Ballistics RN50, were loaded with N130? It's a risky choice for .50" BMG, but it is what you're _supposed_ to use for light bullets in normal-sized sporting rifles! And what if someone had a senior moment and read a tin backwards?
Thank you so much for doing this ! I so very much have wanted to see exactly this . You have the makings for a great desk lamp right there ! 👍 Great work Mark!
Excellent, job well done. Side note on the storm. Remember the one that crossed over Florida and turned around and did it again? Prepare for the worse and hope for the best.
Great vid Mark. Bet the back end of the barrel is intact complete with the breech cap still screwed on it. The way the receiver ruptured looks to be forward considerably of the cap as if that ruptured open and that was the weakest point. The fact that the cap screws onto the end of the receiver seems that it supports it from rupturing the threads and being ejected backwards
If you go through the slomo of the footage @5:50, you can see the explosion leak out of the bottom of the cap where the cap and barrel/breach mate. The threads on the cap failed right there to allow the beginnings of the explosion to leak passed that part of the cap. Because the nature of threads, that part of the barrel/breach probably acted more like a fragmentation grenade and just fragmented which is more why you can't find it.
Both seem possible. The fact the "ears" that support the cap screw were intact seems to indicate Talishar may be right, though. If the threads and cap had remained whole then one would expect the ears to be damaged. All of the above said, truly bizarre things happen when high explosives are involved.
The first sign of the explosive breaching was at the bottom of the chamber/breach cap. As the receiver bent downward. The next frame all you see is explosion, I would hazard a guess that you might look from about 45° aft of perpendicular to somewhere forward of the position. Seemingly to the right as seen from behind. Nice Gideon, thank you!
C4 is small arms fire insensitive. You can shoot it without any detonation. Small arms propellants are NOT small arms safe in bulk over 0.50 kg. It is quite certain to say in the 130 years of smokeless propellants, there have been quite few detonating small arms, even when mercury fulminate was used as priming. This priming compound was removed from smokeless rounds because of the embrittlement of brass from mercury. Sulfur in black powder scavenged the mercury, preventing brass embrittlement. K chlorate (ClO3) was standard priming until 1930s, 1960s in US military, save .30 Carbine amno which was considered less demanding non front line use. Traditions die hard in the military
I hope you're. correct about the hurricane, however the projected routes say you're wrong. Good luck on the storm. I have done some work with explosive forming before and some explosive bolts for rocket stage separations. A little goes a long way.
It would be interesting to see if really small amounts of the C4 could send that round down range at super high speeds(while not fully compromising the platform). 🤔
Most likely not. C4 is a "high explosive" and it's burns so fast that in order to use a safe enough amount, it would be so little that it wouldn't generate enough pressure to push anything down the barrel. Use more, and you have a bomb. It's why firearm powder burn rates are so important.
@@liamthepyro A standard .50bmg primer would probably detonate it. They contain lead styphnate which is a primary HE after all. If not, a tiny pinch of a primary in the base before the charge would set it off every time.
Thats not really how gunpowder works. Speaking as a reloader, the faster burning the propellant is, (generally) the sharper and more violent the pressure spike is - leading to explosive deformation of the breach. For the highest velocity projectile, you want the propellant charge to burn slowly enough to maintain a just under maximum pressure for as long as possible, i.e. the full length of the barrel. Thats the balance of reloading - finding the highest pressure propellant charge that wont exceed the mechanical strength of the barrel, but maintains it's 'burn' for a slow enough amount of time that it's exerting pressure the whole time the bullet is in the barrel. Basically.
It would take a lot. Way more than would be practical as high explosives like c4 dont have very good expansive properties because they explode so fast.
Love your guns , engineering and ingenuity would love to have 1 or 2 of the 50 BMG but the wait time is too unbearable to wait that long to enjoy ranging such beautiful masterpieces 🤣 when build time is down to 3 months or less I would love to aquire 1-2 of your machining technical works of art . 👍
That is awesome! It looked looked like you where try to launch back part Barrel and cap. To me it cap bounced off the rail missing the ears and went straight back.
I would have expected that such an explosive detonation would have propelled the bullet, but it appears that the breech disintegrated first, releasing all of the energy that way. This gives a better comprehension of the effects of putting this explosive into bullets and loading them in AK-47's which were left on trails in Vietnam for enemy soldiers to 'find'.
Did it detonate from the primer being struck like a normal round, or was there another method employed? Just curious, I know nothing about C4 or any explosives outside reloading. I have no idea if the primer could or could not detonate C4, or if it could would it matter if the C4 was contained or not.
Deflagration to detonation tests on common safe explosives are out there. Consider the classic gravity bombs. These are filled at the ammo plant but the fuses are not installed. This is to make the ordnance fire safe. Or safer. From the high speed video and my testing experience, there was very little delay from primer impact to first sign of rupture. C4 is a small arms safe E. Smokeless propellants in bulk are not. Primers have a very low detonation velocity or a very fast deflagration rate. They initiate by heat, not shock. All at normal temperatures. Heat any styphanate primer to initiation and this velocity rises, potentially to a true detonation transisition. Primers are no joke, please do not ever try heating them. They represent the greatest hazard in ammunition fires as some can penetrate standard fire fighter turnout gear. The cup only weighs a few grains but it can achieve supersonic speed if heated to initiation.
On the highspeed closeup it looks like the cap is going towards the side a little. There is a dust cloud to the right of the blue barrel that would fit that aprox. path and size of projectile. Good luck finding it though...
Frame-stepping thru the end of the video, it appears the cap split in half with the top portion going up and rearward while the remainder disintegrated or, at the very least, was forced downward, thru the receiver. Being there are precisely 2 frames showing the moment of detonation, it's hard to determine anything more. I do find it fascinating that the chamber as well as the surfaces where the barrel fractured were instantly brass plated by the pressure.
Yeah, I never understood that. Shit doesn't deflagrate, how does that work? Also: low-vulnerability ammo in general (of which HITP is one type, pretty much) uses high explosive.
We're over on the East coast in Brevard. Not really expecting much here, just some rain & wind. Good luck over there Mark and everyone else in the path of this thing. Hope it's a non-event! Take care.
I wonder if the breech cap has part of the back end of the barrel still threaded into it... Given how it seems to have disintegrated that may be likely.
Under 800 m/s. KNO3/C/S mixtures have low gas volumes as most mass products are solids. Only gases are carbon oxides (di and mono) sulfur oxides and nitrogen. Plenty of potassium oxide and carbonate with minor sulfur carbon compounds. Second, all gases and solids are heavier than typical smokeless propellant products which include water vapor, a very light and ideal gas at the temperature involved. Light molecular weight species have higher sonic velocities and are easier to accelerate.
Hey Mark I am just wondering and curious at this point you stuffed a lot of C-4 in those cartridges is there an extremely small amount of C4 that you could put inside of that cartridge that would make the round perform like a normal round or is the effects from the C4 just to catastrophic even in small quantities
The pressure curve would probably be too high. He posted a video a while back about pistol vs rifle powder pressure curves to try to determine if pistol powder in a 50 BMG case would achieve high enough pressure to sheer off the cap
Fantastic demolition .You need to try using far less explosives like only 1 gram and see what happens.Will the bullet make it out or is the impulse so fast it will do the same thing and grenade
The slow mo footage slow mowed down some more revealed the cap leaving earths atmosphere at a clean 45* angle. You might check mars or the moon. Good luck!
@@Ancient_Yuletide_Carol Based on other comments i have seen about the car, I am surprised at how many people just fail to think about things like driving the car away, and driving the car back after the explosion...people just don't think anymore these days.
To protect you camera use a mirror at 45 degrees to provide even better protection use two mirrors. Any high-speed debris goes through the mirror and bypasses the expensive camera. Interesting pattern of the ripped/torn metal of the barrel versus the smooth rips in Kentucky Ballistics example. Also interesting is the rapid pressure spike so fast that the bullet did not have time to travel down the barrel before catastrophic rupture of the chamber and pressure equalization. Mark - good job of bracketing the pressure ranges of the two examples. Any idea of max pressure from this test?
amazing how the metal fractured, didnt have that grey "smooth" crystaline look you see in lower pressure "rips". Almost looks like it broke in layers and the "Elmer Fudd" spread was rather symetrical... I even replayed at the slowest speed possible and still couldnt see the end cap go anywhere, from what I could "see" it looked like it broke into several pieces but its really hard to tell. The brass was imbedded into the barrel from the looks of it. Just amazing the power of a solid going into its gas component molecules in nano seconds.... just WOW!!
In one of Gen. Hatcher's books he relates the tale of a guy who reloaded a 12 ga. shotgun shell with sensitive dynamite and got his cheating and heavily-insured wife to shoot it. Results were very similar but many action parts were not recovered. The woman was killed instantly. It was ruled an accident until the greedy bastard tried to sue the ammo and gun manufacturers, who quickly proved it was caused by high explosives. The man got the electric chair, which sizzled but did not explode, unfortunately.
No there's definitely high explosives that are shock sensitive, Nitroglycerin for instance. Difference between high explosives and low explosives is that the shock wave of a high explosive moves faster than the speed of sound(detonation) while a low explosive's wave moves slower than the speed of sound (deflagration). Shock sensitivity doesn't play into the speed of their shock wave directly, though more sensitive compounds tend to be more energetic.
Thank you mark. It’s the video they all needed., it does however, revisit the question , just how much was in that slap round… would a minor miscalculation in loading be enough to reach the barrel pressure we saw with Scott .. or is it of a quantity that …you would have to be aware? I know it was pistol powder, but I’m trying to ask: If x amount of regular powder was swapped for the same amount in pistol powder… would that be enough for the failure we saw? … OR would you have to intentionally OVER load it to get there. ? If the load of pistol powder needed to reach those pressures exceeds the amount we would other wise regularly use, I would start to suspect it was more likely intentional. Full disclosure I’m suspicious by nature… but the question is valid.
Mark, i have wonder since you made your cheaper 50 cal why you didn't just make it a breach loader instead with that cap that isnt very intuitive in the loading unloading process
I have a question, because C4 is a high-velocity explosive, shouldn't you put something like less than 1/3% of the normal amount of propellant or even less so that the expanded gases don't explode the barrel?
It looked like in that first frame of the explosion, the fire was shooting through the cap's firing pin, so if that was the bulk of the explosion, I don't think you'll ever find the cap, it was probably torn apart like the barrel
"it recocked the hammer"
So you're telling me this was a semi-auto RN50 for a split-second?
Forced reset trigger lol it's a machinegun. Settle down ATF, this was a joke.
I'll hazard a guess the breech plug may have flown over the wood boards because recocking the hammer changed its trajectory.
Split second, split barrel, split breach plug. You name it.
New type of action. Someone call gun Jesus.
Direct blast back
Mark don’t be a chicken, pick up the hot metal. It’s kinky like u like it
Its for science.
It brings a new meaning to the word, "Smithereens."
It makes me think of "to shreds you say?"
Oh myy
Smitherinies!
4:53 The way the steel of the barrel sheared is absolutely *terrifying* - because it's sheared, not burst open. The steel didn't even have the time to BEND.
The C4 tore the steel like paper
Well I think we can safely say that the SLAP round that Scott fired was definitively not C4 spiked. The damage was totally diferent in appearance. I know its expensive but could you blow the next one up with pistol powder and analyze the results?? Also It would be better if done in a contained area so its easier to retrieve the parts for said analysis. A lined 20' shipping container perhaps. Many thanks for this Mark. I really appreciate your diligence in solving the SLAP mystery. On top of that you are getting some nice high speed physics footage in the process. Give the SloMo guys a call and see if you could get a collab going. I'm pretty sure they would be interested in the solve the SLAP mystery too. I know I would if I had the tools! Take care stay safe. Jimbo.
It was already solved.
@@James_Bee True, but no one has done it with a respectable high-speed yet. 17,000 frames per second is nowhere near enough.
C4 was never even an option. C4 is only detonated with a blasting cap at like 50,000 fps shock wave. The pressure inside the rifle isn't even enough to detonate C4.
@@bobbygetsbanned6049 unlike at 5:47 when the pressure inside the rifle detonated the C4
@@benhemmings1290 c4 is detonated by a small shape charge called a blasting cap. They showed it blowing up without a barrel first.
The detonation velocity of around 26,000 feet per second makes steel react like putty; the coolest thing is how the breech was gone so fast that the bullet barely moved. If you run another experiment you should invite Edwin over so he can pick up all the hot pieces.
🤣🤣🤣
This reminds me of the "cap confinement tests" we would perform on potential explosives (safety testing in a chem lab). Basically, a five to seven gram sample (depending on density) would be (very carefully) tamped into a bore in an aluminum round and topped off with a blasting cap. The resulting mini pipe bomb would be wired up and buried in a one cubic yard sand box (made from railroad ties) and then popped. High explosives (detonants) would shatter the aluminum round into sand sized particles, while low explosives (deflagrants) would deform and tear it, like an over-inflated balloon.
This is helping me more and more dismiss the idea of a sabotaged round in Scott’s accident and be more and more comfortable with it being a hot load using pistol powder. Thank you Mark for your tireless work.
I honestly thought the last couple of vids proved that beyond any doubt, yet here we are.
@@James_Bee they really did, but this basically puts a nail in the coffin.
The sabotaged round theory never really made sense, unless it was a deliberate attack on Scott, which there's zero evidence for. The idea that there would only be a single sabotaged round in circulation in the US that Scott happened to get seems highly unlikely. More likely, there would have been multiple rounds in circulation, with multiple explosions resulting.
C4 really could be dough. In Swedish, plastic explosives are called _"sprängdeg"_ which would translate as _"explosive dough"_ or outright _"blowdough"_
is "blowdough" the more direct translation? I'm amazed English speakers don't call it that anyway that's great.
@@samrowland2816 The most literal I can think of.
Sprengteig... loool
Officer: "Sir, is that cocaine in these ziploc baggies?"
Mark: "No sir, officer, sir."
Also Mark: "It's C4"
No sir it's Blow dough!!
It's just spicy Parmigiano
You flirted around it in the last video, but nerding out about matching the velocity of detonation of an explosive to the job at hand was one of my favorite parts of blasting.
Needless to say, the velocity of detonation of any explosive or blasting agent is too high for a rifle. 🤣 Super interesting videos, and you do a great job narrating and talking. Thanks Mark!
That powderized casing says a lot about power and velocity of failure is impressive! I'm also amazed at that grain structure, it's just art.
I find it so amazing C4 can do such damage; yet it just burns in a very controlled fashion if not initiated with a primary explosive.
Burning is the official way to dispose of TNT.
Looks like the breach cap was blown up at a near vertical angle, possibly to the right also.
I have seen explosions/detonations of other guns with rear pieces can going upwards and a little bit forward. If the material initially breaks at the bottom/ventral surface but is still attached momentarily for a millionth of a second the piece can swing in an arc from where it is still attached and as the last part of material lets go end going into the air and actually end up of forward of the gun.
At .25 speed I could just barely see that.
@@loquat44-40 It does appear on the video that the cap separated at the bottom first, allowing it to do just just that. It's amazing how the ears stayed intact though.
@@freeman2399 Yep! That's why I figure the Cap is somewhere Forward of the explosion.
I once saw a .45 Colt revolver blow out the cylinder from a significant 'Undercharge' the light target load had the powder in two piles within the case at the moment of ignition. The two 'piles' started two flamefronts that collided in the middle of the case causing it to blow. BTW, That's why detonation in a car engine with cheap gas will tear an engine up so badly!
Nice video and cool explosion! You must have inserted a 'Fuse ignition blasting cap' into the case to be lit by the primer. Pretty Cool! Ya'll Take Care and be safe, JohnDF
I want to know what hit the ground on the far side of the steel drum lying to the right of the setup. Whatever it was, it was moving mighty fast.
Honestly,didn't expect video to be exciting,because it was short,but you've just made a video that gets straight to the point.
Good job,enjoyed it.
In the last high speed clip, you can kind of track the cap... the trouble with high explosives is the pressure curve is so sharp you'll damage things before the pressure reaches something intended, and if you wanted to test the ears that kind of happened here. The entire receiver flexed as the cap and threads cracked off the barrel and it flowered, and you can see the cap tilt to about 60 degrees before being obscured, but... then you can see a fireball exiting the view at about a 30 degree angle, that's probably the cap shrouding some hot gasses and side products.
I'd bet it made it one or two hundred yards, but it's intact out there somewhere...
Thank you for talking so real it makes your videos so great to watch.
Nothing more fun than C-4. It is amazing just how powerful such a small amount of explosives can be. Stay safe Mark, we are hunkering down for the blow. At least I won't have to water my grass for a few days. Semper Fi.
So is it just the primer that detonated the c4 or was there also a low explosive used ? I didn’t think a primer would be enough to set it off reliably
Mark would be wise to keep such details out of the public.
This was an extreme boundary test. Next would be a case full of N310 to match the accident results.
There have been many tests proving a true detonation in a firearm is nearly impossible. Over pressure events are common. Been there, twice. The case fails, the ensuing jet of 50,000 PSI gas at over 6000°F vaporizes brass, coating surrounding cool metal with a golden vapor deposit. Loss of case structure overloads bolt features and causes expansive deformation until pressure subsides.
Even the mild .22 long rifle does significant damage on case failure. It shatters magazines, opens bolt faces and shucks extractors.
If you want to make it go boom reliably, just put a layer of primary (silver acetylide, PbN6, fulminate, whatever) between primer and C4.
Most primer mixtures seem to contain lead styphnate, question is whether it detonates or just burns extremely fast upon primer strike.
Detonation likely would provide enough pressure to detonate C4, whereas fast burning stuff does not.
Primary detonates no matter what, setting off the C4.
I'd be using something like lead azide on top of the primer. The primer wouldn't be enough to detonate the c4, you definitely need a strong primary explosive.
Great information Mark! Thank you and hope the weather doesn't screw up your week!
Mark, you're awesome! I hope that you're okay through the hurricane too!
It looks like the breach cap is in multiple peaces because the initial blast looked like it came out the Firing pin assembly in the cap button I would not be looking for a complete cap also it looks like the chamber parted in the centre you could see a lovley chunk of it making its way through the smoke thankyou for the video
Now, Mystic Meg's daily stars a few days ago, did tell me not to say "I told you so." But let's just say that it was predicted in the comments section of a previous video that a cartridge filled with an actual high explosive (as in a "spiked" round), rather than a pistol powder, would cause the gun to disintegrate around the breech into splinters of metal rather than component parts. Don't waste too much time looking for the breech cap: it is probably an ex breech cap, it has ceased to be. High explosives do a different _kind_ of damage. I doubt that you could use small amounts of high explosive to propel bullets at high speeds: even if the barrel was inches thick, the inner bore would shatter even if the outside diameter was so wide it didn't even bulge.
PS: If cast HMX had been employed instead of C4, you'd be looking at smaller splinters.
PPS: The suspect pistol powder is Vihtavuori N310. What if the other cartridges, which were hot but did not blow up the Kentucky Ballistics RN50, were loaded with N130? It's a risky choice for .50" BMG, but it is what you're _supposed_ to use for light bullets in normal-sized sporting rifles! And what if someone had a senior moment and read a tin backwards?
To your PPS: That's a very good hypothesis! Maybe if Mark has more "factory second" parts, he'll test this.
@@rgnglzrd It might not even be a destructive test, in an RN50. But a semi-auto might cycle hard and eject with violence.
Breach cap went up and to the left from the looks of it could be wrong but that what it looks like happened. Thank for the experiment Mark
Thank you so much for doing this ! I so very much have wanted to see exactly this . You have the makings for a great desk lamp right there ! 👍
Great work Mark!
Hello from Detroit Michigan brother thank you for sharing your knowledge and expertise and for what you do
Excellent, job well done. Side note on the storm. Remember the one that crossed over Florida and turned around and did it again? Prepare for the worse and hope for the best.
Great vid Mark. Bet the back end of the barrel is intact complete with the breech cap still screwed on it. The way the receiver ruptured looks to be forward considerably of the cap as if that ruptured open and that was the weakest point. The fact that the cap screws onto the end of the receiver seems that it supports it from rupturing the threads and being ejected backwards
If you go through the slomo of the footage @5:50, you can see the explosion leak out of the bottom of the cap where the cap and barrel/breach mate. The threads on the cap failed right there to allow the beginnings of the explosion to leak passed that part of the cap. Because the nature of threads, that part of the barrel/breach probably acted more like a fragmentation grenade and just fragmented which is more why you can't find it.
Both seem possible. The fact the "ears" that support the cap screw were intact seems to indicate Talishar may be right, though. If the threads and cap had remained whole then one would expect the ears to be damaged.
All of the above said, truly bizarre things happen when high explosives are involved.
Mark, you have the best job going! If I lived in the Tampa area, I would want to hang out with you!
The first sign of the explosive breaching was at the bottom of the chamber/breach cap. As the receiver bent downward. The next frame all you see is explosion, I would hazard a guess that you might look from about 45° aft of perpendicular to somewhere forward of the position. Seemingly to the right as seen from behind.
Nice Gideon, thank you!
Love your curiosity to see how things behave❤️
Ok, that was awesome. Proper salted round that is. 👌Looking forward to the sciency video now!
Looks like the casing also partially explosion welded to the chamber.
Very interesting.
Mark and angry play dough/serious putty, awesome video!
I live in East TN. I think I found the breach cap in my front yard.
I always wondered if a normal primer would be sufficient to get C4 to detonate, seems so.
.50BMG primers are bigger and stronger than normal rifle primers, mind.
C4 is small arms fire insensitive. You can shoot it without any detonation. Small arms propellants are NOT small arms safe in bulk over 0.50 kg.
It is quite certain to say in the 130 years of smokeless propellants, there have been quite few detonating small arms, even when mercury fulminate was used as priming. This priming compound was removed from smokeless rounds because of the embrittlement of brass from mercury. Sulfur in black powder scavenged the mercury, preventing brass embrittlement. K chlorate (ClO3) was standard priming until 1930s, 1960s in US military, save .30 Carbine amno which was considered less demanding non front line use. Traditions die hard in the military
That's assuming that there wasn't something else in the cartridge.
Excellent video and shocking results from such small amount! 👍
The Forbidden Play Dough
I hope you're. correct about the hurricane, however the projected routes say you're wrong. Good luck on the storm.
I have done some work with explosive forming before and some explosive bolts for rocket stage separations. A little goes a long way.
Cool Video Mark! Keep up the lords work. Love my BMG50
You have way too much fun at work!
It would be interesting to see if really small amounts of the C4 could send that round down range at super high speeds(while not fully compromising the platform). 🤔
Most likely not. C4 is a "high explosive" and it's burns so fast that in order to use a safe enough amount, it would be so little that it wouldn't generate enough pressure to push anything down the barrel. Use more, and you have a bomb. It's why firearm powder burn rates are so important.
No. Probably not.
@@liamthepyro A standard .50bmg primer would probably detonate it. They contain lead styphnate which is a primary HE after all. If not, a tiny pinch of a primary in the base before the charge would set it off every time.
Thats not really how gunpowder works. Speaking as a reloader, the faster burning the propellant is, (generally) the sharper and more violent the pressure spike is - leading to explosive deformation of the breach.
For the highest velocity projectile, you want the propellant charge to burn slowly enough to maintain a just under maximum pressure for as long as possible, i.e. the full length of the barrel.
Thats the balance of reloading - finding the highest pressure propellant charge that wont exceed the mechanical strength of the barrel, but maintains it's 'burn' for a slow enough amount of time that it's exerting pressure the whole time the bullet is in the barrel. Basically.
It would take a lot. Way more than would be practical as high explosives like c4 dont have very good expansive properties because they explode so fast.
Great video a curiosity answered and quite an amazing after effect. I was expecting damage but not that much
Love your guns , engineering and ingenuity would love to have 1 or 2 of the 50 BMG but the wait time is too unbearable to wait that long to enjoy ranging such beautiful masterpieces 🤣 when build time is down to 3 months or less I would love to aquire 1-2 of your machining technical works of art . 👍
That is awesome! It looked looked like you where try to launch back part Barrel and cap. To me it cap bounced off the rail missing the ears and went straight back.
I would have expected that such an explosive detonation would have propelled the bullet, but it appears that the breech disintegrated first, releasing all of the energy that way.
This gives a better comprehension of the effects of putting this explosive into bullets and loading them in AK-47's which were left on trails in Vietnam for enemy soldiers to 'find'.
As Scott would have said ....that is spicy. Dang, that was amazing. Can't wait to order mine.
Thank you for the video, Mr.Serbu! Now, can i have that barrel? I will pay for the shipping! Thank you very much, stay safe and have a blessed one!
Did it detonate from the primer being struck like a normal round, or was there another method employed? Just curious, I know nothing about C4 or any explosives outside reloading. I have no idea if the primer could or could not detonate C4, or if it could would it matter if the C4 was contained or not.
Deflagration to detonation tests on common safe explosives are out there. Consider the classic gravity bombs. These are filled at the ammo plant but the fuses are not installed. This is to make the ordnance fire safe. Or safer.
From the high speed video and my testing experience, there was very little delay from primer impact to first sign of rupture.
C4 is a small arms safe E. Smokeless propellants in bulk are not.
Primers have a very low detonation velocity or a very fast deflagration rate. They initiate by heat, not shock. All at normal temperatures.
Heat any styphanate primer to initiation and this velocity rises, potentially to a true detonation transisition. Primers are no joke, please do not ever try heating them. They represent the greatest hazard in ammunition fires as some can penetrate standard fire fighter turnout gear. The cup only weighs a few grains but it can achieve supersonic speed if heated to initiation.
That is a cool, fun video!
And educational as well!
Thanks!
On the highspeed closeup it looks like the cap is going towards the side a little. There is a dust cloud to the right of the blue barrel that would fit that aprox. path and size of projectile. Good luck finding it though...
Frame-stepping thru the end of the video, it appears the cap split in half with the top portion going up and rearward while the remainder disintegrated or, at the very least, was forced downward, thru the receiver. Being there are precisely 2 frames showing the moment of detonation, it's hard to determine anything more.
I do find it fascinating that the chamber as well as the surfaces where the barrel fractured were instantly brass plated by the pressure.
The caseless ammo developed by H&K for the G11 was based on RDX/hexogen which is the main component of C4.
Yeah, I never understood that. Shit doesn't deflagrate, how does that work? Also: low-vulnerability ammo in general (of which HITP is one type, pretty much) uses high explosive.
3:00 Hard chuckle lolll! Funny how some things are meant for some layers while others appreciate from outside of the boundry.
We're over on the East coast in Brevard. Not really expecting much here, just some rain & wind. Good luck over there Mark and everyone else in the path of this thing. Hope it's a non-event! Take care.
would love to know all the nerdy stuff, the forces put on the barrel and the physics involved is always mind bending
Not to get too nerdy & technical, but it scientifically buttfucked it into little pieces.
That video sure was a blast to watch!
I saw it! It went over there, over there, over there, over there, over there, up there, over there, and up there.
I wonder if the breech cap has part of the back end of the barrel still threaded into it...
Given how it seems to have disintegrated that may be likely.
Hello Mark! I have a question I hope you would adress: how fast would a black powder loaded 50 BMG go out of RN50?
Under 800 m/s. KNO3/C/S mixtures have low gas volumes as most mass products are solids. Only gases are carbon oxides (di and mono) sulfur oxides and nitrogen. Plenty of potassium oxide and carbonate with minor sulfur carbon compounds.
Second, all gases and solids are heavier than typical smokeless propellant products which include water vapor, a very light and ideal gas at the temperature involved. Light molecular weight species have higher sonic velocities and are easier to accelerate.
I rarely comment but after watching I noticed I was not subscribed. I've been a subscriber for over a year.
had you done this in Hollywood it would have left a 50ft hole in the ground.
Thank you Mark.
Hey Mark I am just wondering and curious at this point you stuffed a lot of C-4 in those cartridges is there an extremely small amount of C4 that you could put inside of that cartridge that would make the round perform like a normal round or is the effects from the C4 just to catastrophic even in small quantities
The pressure curve would probably be too high. He posted a video a while back about pistol vs rifle powder pressure curves to try to determine if pistol powder in a 50 BMG case would achieve high enough pressure to sheer off the cap
Awesome video! Are my eyes deceiving me, or does the (newly-renovated) chamber show the brass from the cartridge-casing basically smeared all around?
"Angry playdough"
lol angry playdough 😂
I love how you're leaning into the "blow up my guns in new and interesting ways." 😂
Fantastic demolition .You need to try using far less explosives like only 1 gram and see what happens.Will the bullet make it out or is the impulse so fast it will do the same thing and grenade
Looks like Elmer Fudd's shotgun now! But could C4 be used in a revolver round?
It's a collab between Elmer Fudd and Yosemite Sam
The slow mo footage slow mowed down some more revealed the cap leaving earths atmosphere at a clean 45* angle. You might check mars or the moon. Good luck!
lol im also surprised your car is parked so close, was waiting for a "is that a hole in the windshield?"
@@Ancient_Yuletide_Carol Based on other comments i have seen about the car, I am surprised at how many people just fail to think about things like driving the car away, and driving the car back after the explosion...people just don't think anymore these days.
hm. what would c4 22lr do?
Exactly the same.
nice experiment Mark.
I know a few people who would see this and warn me about the squibed round as if you could put another round through that rifle.
Squibed round AND re-cocked.
It's one trigger pull away from blowing up.
If you can find the trigger....
That was exactly how you explained it would be in your last video. I think the end cap disintegrated along with the end of the gun barrel.
I'd love the slow mo guys to come around and whip out the Phantom Camera for these explosions.
Gotta love the "Angry Silly Puddy"
The explosion,the fire, destruction and devastation! I don't know if It's art but I know what I like 👍
To protect you camera use a mirror at 45 degrees to provide even better protection use two mirrors. Any high-speed debris goes through the mirror and bypasses the expensive camera.
Interesting pattern of the ripped/torn metal of the barrel versus the smooth rips in Kentucky Ballistics example. Also interesting is the rapid pressure spike so fast that the bullet did not have time to travel down the barrel before catastrophic rupture of the chamber and pressure equalization.
Mark - good job of bracketing the pressure ranges of the two examples. Any idea of max pressure from this test?
yup, they used mirrors to record the moon rocket launches in the 1960s
Wowza!
Welp, looks like you definitely put the nails in the coffin over the "Eldest Son" round theory.
amazing how the metal fractured, didnt have that grey "smooth" crystaline look you see in lower pressure "rips". Almost looks like it broke in layers and the "Elmer Fudd" spread was rather symetrical... I even replayed at the slowest speed possible and still couldnt see the end cap go anywhere, from what I could "see" it looked like it broke into several pieces but its really hard to tell. The brass was imbedded into the barrel from the looks of it. Just amazing the power of a solid going into its gas component molecules in nano seconds.... just WOW!!
In one of Gen. Hatcher's books he relates the tale of a guy who reloaded a 12 ga. shotgun shell with sensitive dynamite and got his cheating and heavily-insured wife to shoot it. Results were very similar but many action parts were not recovered. The woman was killed instantly. It was ruled an accident until the greedy bastard tried to sue the ammo and gun manufacturers, who quickly proved it was caused by high explosives. The man got the electric chair, which sizzled but did not explode, unfortunately.
Hope you fair well with the weather
That's some Wile E Coyote level prank there!
Looks like the cap had an exit angle just high enough to clear the plywood... Or it was deconstructed.
Really interesting, so the normal primer was enough to set off the C4?
No there's definitely high explosives that are shock sensitive, Nitroglycerin for instance.
Difference between high explosives and low explosives is that the shock wave of a high explosive moves faster than the speed of sound(detonation) while a low explosive's wave moves slower than the speed of sound (deflagration).
Shock sensitivity doesn't play into the speed of their shock wave directly, though more sensitive compounds tend to be more energetic.
The breech cap actually went into another dimension
Thank you mark. It’s the video they all needed., it does however, revisit the question , just how much was in that slap round…
would a minor miscalculation in loading be enough to reach the barrel pressure we saw with Scott .. or is it of a quantity that …you would have to be aware?
I know it was pistol powder, but I’m trying to ask:
If x amount of regular powder was swapped for the same amount in pistol powder… would that be enough for the failure we saw? … OR would you have to intentionally OVER load it to get there. ?
If the load of pistol powder needed to reach those pressures exceeds the amount we would other wise regularly use, I would start to suspect it was more likely intentional.
Full disclosure I’m suspicious by nature… but the question is valid.
The grain structure of that barrel looks the same as when you find a large piece of shrapnel from a 155 round! Take Care, JohnDF
So primers can reliably detonate C4? Or did you do something different?
I'm surprised the ears on the frame stayed there, stayed intact.
Makes me wonder just how hot those rounds KB got actually were.
I had thought this was a possibility in the beginning but this clearly shows it was not what caused the accident.
That breech cap is in a whole different zip code. 😂
The breech cap landed in my backyard.
I'm on the California coast.
Mark, i have wonder since you made your cheaper 50 cal why you didn't just make it a breach loader instead with that cap that isnt very intuitive in the loading unloading process
Do you think you could make a barrel strong enough to fire one of those C4 rounds. What kind of muzzle velocity would a round like that have.
I have a question, because C4 is a high-velocity explosive, shouldn't you put something like less than 1/3% of the normal amount of propellant or even less so that the expanded gases don't explode the barrel?
if that's what 22 grams does, would a charge around 1 gram keep the gun intact and send the bullet? Interesting video.
It looked like in that first frame of the explosion, the fire was shooting through the cap's firing pin, so if that was the bulk of the explosion, I don't think you'll ever find the cap, it was probably torn apart like the barrel