You'd need a certain amount of fissile material to even get a thermonuclear device going. That certain amount is in the kilograms instead of grams. Bullets are on the scale of a few grams. No critical amount of fissile material? No boom boom.
It’s kind of incredible that the critical mass of fissile material is on the order of double digit kilograms, a workable amount that fits nicely in the arsenal of states as a step above everything else. What luck, huh? It could have just as easily been several orders of magnitude higher, to where the smallest nuke could destroy a country, or magnitudes smaller, to where we’d have nuclear 5.56 bullets.
Early nuclear projects and experiments spent quite a bit of time and money figuring that out. I think some even wrongly concluded that it might be hundreds or thousands of kilos, which would have been pretty impossible to produce at the time.
A few German nuclear scientists captured by the US couldn't believe the US had managed to produce even kilograms of the stuff. The scale of the effort was really something at the time.
I mean, it's no more lucky or unlucky than our planet somehow having the exact atmospheric disposition, climate etc. to make human life possible to evolve.
The M-28 davy crockett is as small as a nuke can scale down. Antimatter HE rounds might be theoretically possible, pray that containment doesn't fail.
It’s kind of incredible that the critical mass of fissile material is on the order of double digit kilograms, a workable amount that fits nicely in the arsenal of states as a step above everything else. What luck, huh? It could have just as easily been several orders of magnitude higher, to where the smallest nuke could destroy a country, or magnitudes smaller, to where we’d have nuclear 5.56 bullets.
Fricked if I can find it now but there was a great interview with a nuke designer in the 90s. He was asked "what's the smallest functional nuke you have tested" his answer was "while the exact size is classified I can say it was closer to a grenade than a basketball".
Gun types can be tiny because no lens, no minimum sub-criticallity for safety and you can get away with firing the core with a reflector already attached.
>M-28 davy crockett is as small as a nuke can scale down
No. The M-28's warhead has 23.1kg of fissile material. This is slightly less than the IAEA's definition of a "significant quantity," which is 25kg, but neither represents the theoretical lower limit of fissile material necessary to create an implosion-type warhead. That lower limit is almost assuredly still way larger than a rifle round, though, even if Teller wasn't bluffing with the theoretical minimum size of a Teller-Ulam device.
There was a paper that came out in recent years on pure fusion weapons that suggested you could make a nuke out of steel casing, explosive lenses and some gas. However, it's STILL extremely heavy because the casing has to be heavy steel to prevent the explosive lenses from simply ripping the bomb apart. On the other hand, it got the 'minimum size' down to something like 30cm long and 15cm wide, with zero fissionables needed.
No idea if the paper was full of shit or not, though.
>?useskin=vector
Is there a userscript or something that adds this automatically to wikipedia links?
I made an account to revert the skin for myself but I don't want others to suffer when I'm sharing wikipedia links.
Didn't the early gun-type fission bomb work a bit like this? It combined a cylinder and a precisely shaped ring of material quickly using explosives to form a critical mass, or something like that.
It was horribly inefficient, though. Almost all of the material would just scatter.
As others said no. Or at least not without some exotic matter or antimatter type of system if you want to get scifi-y in your definition of "theoretical". Like if it was somehow possible to produce stable trit with muons instead of electrons. But it probably isn't and if it is it's far far beyond what we can do. There is the limiting factor problem too: if a civilization has got that kind of supertech do rifles even still exist and have a role in their present form? Probably not.
Yes Little Boy was a U-235 gun type bomb, and yeah the efficiency is dogshit, can't use plutonium which is also a PITA, it's very big etc. Reliable and simple but there is a reason absolutely everyone moved on instantly, it was only a hedge just in case since it was being used in an actual shooting war and fat man wasn't 100% certain proven yet. Whereas they were completely sure Little Boy would work.
I considered it might be possible if a bullet was going at speeds of 300 km/s and was made of paraffine or something similar. It might cause a nuclear detonation if it hits a person
>nuclear explosions
E = mc^2 >accelerate shit to relativistic velocities
Ek = 0.5mv^2
At best you can approach half of the energy.
That said, the famous mass-energy equivalence formula doesn't really apply to nuclear reactions despite often used in that context. Only to matter-antimatter annihilations.
You forget that shit stops being classical after a few percentages of the speed of light, and at that point become more relativistic instead
Weird things happen when time seems more like a suggestion and the concept of simultaneous events doesn't exist anymore
If you accelerate a single hydrogen atom close enough to the speed of light, you'll eventually end up with a black hole
>Ek = 0.5mv^2
That's the non-relativistic part of the equation. At silly enough velocities it is dwarfed by the relativistic part; as the object's velocity approaches c the energy approaches infinity.
That said, I'm not sure what's scarier, a tiny particle flying at a fraction of the speed of light, or the machine that performed the acceleration (presumably with less than 100% efficiency).
I really didn't want to try writing the relativistic part on PrepHole.
And it doesn't differ from the classical part much before you get into ridiculously high fractions of c, over 60%
>Ek = 0.5mv^2
That's the non-relativistic part of the equation. At silly enough velocities it is dwarfed by the relativistic part; as the object's velocity approaches c the energy approaches infinity.
That said, I'm not sure what's scarier, a tiny particle flying at a fraction of the speed of light, or the machine that performed the acceleration (presumably with less than 100% efficiency).
Although another tradeoff is that really small ones tend to require more exotics to get much bang which means their shelf life is lower and they need refurbishment more often. A super basic full size gun type would be good for decades if not a century, to some extent limited by the high explosives, just sitting untouched some cool/dry. The yield for the heaviness is kind of shit tho. The smaller and more efficient the more upkeep in general. A rifle launched grenade maybe could go far enough to avoid killing the operator 100% of the time in principle but if it needed to be rebuilt every few years the logistics would be impossible.
Yes they are theoretically possible but way beyond any capability we possess even in the somewhat distant future. Nuclear fission reactions are basically an issue of probability, the higher the probability of neutrons hitting enriched uranium, the greater the chance it will result in a chain reaction and a full nuclear explosion. Nukes utilize neutron reflectors to achieve critical mass without necessarily requiring the textbook amount, these reflectors will increase the probability neutrons will bounce around and hit u235 atoms, thereby reducing the overall uranium required to achieve a nuclear blast. Suppose we somehow manage to find a material that can perfectly reflect all neutrons it comes into contact with, then a bullet sized u235 sample shrouded by that reflector, and imparted with a free neutrons would certainly cause a nuclear explosion.
>are nuclear rifle rounds theoretically possible?
Oh boy they're not just possible (though it's not a normal rifle but a large recoilless smoothbore) the mad men built them. 20 ton TNT equivalent nuclear devices launched a whole 1.25 to 2.5 miles away.
>with a 100% instant casualty radius in excess of 160 metres (520 ft). The shell's greatest effect would have been its extreme prompt neutron radiation which would have killed most of the enemy troops inside that circle within minutes. Its blast would do very little if any damage to the enemy's tracked vehicles. Troops further away would have died within hours, days and less than two weeks depending on their range from the point of burst and the thickness of their protection.
this time period in american history was pretty fricking insane because the nuclear deterrent strategy was basically being so insane that the soviets wouldn't even try to play ball. the problem is that the soviets were probably the only people crazier than the trilateral commision
the general idea was that a full scale war would devolve into the soviets suicide zerg rushing the continental US with hundreds long range strategic bombers packed to the brim with nukes and this was like 20 years before they had even invented guided missiles let alone avionics packages and radar systems, the solution to that was to nuke them in the air and there was only one plane big enough to do that
the b-58 huslter being basically the dumbest plane ever built because it sacrificed everything to go vaguely fast in a straight line to shoot one nuclear bottle rocket and was obsolete within like five years because they figured out how to guide missiles
Our species will always amuse me with how we can make the dumbest shit that still technically works, sure in a hyper specific scenario, but there you are. What, you want to dunk on the Russians using a NUCLEAR POWERED ramjet? Project Pluto. A(probably) function plasma weapon that’s really only useful in space? MARAUDER. The US MIC are wizards and no one can convince me otherwise
>A(probably) function plasma weapon that’s really only useful in space? MARAUDER
Wrong. The smoke ring principle of stabilization used by MARAUDER only works in an atmosphere. In space you want a nuclear shaped charge if you're going to shoot plasma for offensive purposes.
A nuclear salt water rocket, if proven to work, could perhaps be repurposed as a multiple-use nuclear plasma cannon in space. It'll still be short ranged because the charged plasma particles will repel each other unless you manage to neutralize them first, so a shaped charge nuke warhead on your torpedoes make more sense.
According to the internet. In the 50s, suitcase bomb development created a roughly 5 inch implosion device and detonated to create .19kt or 190 tons of tnt. However with the amount of primary explosive necessary to facilitate a nuclear reaction the suitcase still weighed roughly 100 pounds.
https://en.m.wikipedia.org/wiki/Davy_Crockett_(nuclear_device)
The mini nuke davy Crockett was smaller still. And generated a .02kt or 20 ton explosion and still weighed 75ish pounds with its primary explosive and propellant. But it's about as small as they've made them. You could possibly get even smaller if you just use some high speed mass driver to assist in getting the chain reaction underway. But then you'd be dealing with a large shooty
No.
Why not?
You'd need a certain amount of fissile material to even get a thermonuclear device going. That certain amount is in the kilograms instead of grams. Bullets are on the scale of a few grams. No critical amount of fissile material? No boom boom.
It’s kind of incredible that the critical mass of fissile material is on the order of double digit kilograms, a workable amount that fits nicely in the arsenal of states as a step above everything else. What luck, huh? It could have just as easily been several orders of magnitude higher, to where the smallest nuke could destroy a country, or magnitudes smaller, to where we’d have nuclear 5.56 bullets.
Early nuclear projects and experiments spent quite a bit of time and money figuring that out. I think some even wrongly concluded that it might be hundreds or thousands of kilos, which would have been pretty impossible to produce at the time.
A few German nuclear scientists captured by the US couldn't believe the US had managed to produce even kilograms of the stuff. The scale of the effort was really something at the time.
I mean, it's no more lucky or unlucky than our planet somehow having the exact atmospheric disposition, climate etc. to make human life possible to evolve.
Fricked if I can find it now but there was a great interview with a nuke designer in the 90s. He was asked "what's the smallest functional nuke you have tested" his answer was "while the exact size is classified I can say it was closer to a grenade than a basketball".
Gun types can be tiny because no lens, no minimum sub-criticallity for safety and you can get away with firing the core with a reflector already attached.
Becasue critical mass.
No, the physics doesn't work.
It exists
The M-28 davy crockett is as small as a nuke can scale down. Antimatter HE rounds might be theoretically possible, pray that containment doesn't fail.
>M-28 davy crockett is as small as a nuke can scale down
No. The M-28's warhead has 23.1kg of fissile material. This is slightly less than the IAEA's definition of a "significant quantity," which is 25kg, but neither represents the theoretical lower limit of fissile material necessary to create an implosion-type warhead. That lower limit is almost assuredly still way larger than a rifle round, though, even if Teller wasn't bluffing with the theoretical minimum size of a Teller-Ulam device.
There was a paper that came out in recent years on pure fusion weapons that suggested you could make a nuke out of steel casing, explosive lenses and some gas. However, it's STILL extremely heavy because the casing has to be heavy steel to prevent the explosive lenses from simply ripping the bomb apart. On the other hand, it got the 'minimum size' down to something like 30cm long and 15cm wide, with zero fissionables needed.
No idea if the paper was full of shit or not, though.
M107 nuclear tank found when?
https://en.wikipedia.org/wiki/Critical_mass?useskin=vector#Critical_mass_of_a_bare_sphere
no
>?useskin=vector
Is there a userscript or something that adds this automatically to wikipedia links?
I made an account to revert the skin for myself but I don't want others to suffer when I'm sharing wikipedia links.
yeah, on greasyfork there are several
Thanks mate.
Depleted uranium counts?
C-can you shoot into a piece not big enough for nuclear reaction, with a nuclear bullit, so it would reach critical mass on impact?
That is the original method for generating nuclear explosions, anon.
Didn't the early gun-type fission bomb work a bit like this? It combined a cylinder and a precisely shaped ring of material quickly using explosives to form a critical mass, or something like that.
It was horribly inefficient, though. Almost all of the material would just scatter.
As others said no. Or at least not without some exotic matter or antimatter type of system if you want to get scifi-y in your definition of "theoretical". Like if it was somehow possible to produce stable trit with muons instead of electrons. But it probably isn't and if it is it's far far beyond what we can do. There is the limiting factor problem too: if a civilization has got that kind of supertech do rifles even still exist and have a role in their present form? Probably not.
Yes Little Boy was a U-235 gun type bomb, and yeah the efficiency is dogshit, can't use plutonium which is also a PITA, it's very big etc. Reliable and simple but there is a reason absolutely everyone moved on instantly, it was only a hedge just in case since it was being used in an actual shooting war and fat man wasn't 100% certain proven yet. Whereas they were completely sure Little Boy would work.
How the frick are you going to fit critical mass of anything into a rifle bullet?
I considered it might be possible if a bullet was going at speeds of 300 km/s and was made of paraffine or something similar. It might cause a nuclear detonation if it hits a person
Tfw your velocities are measured in percentages of the speed of light
Aren't nuclear explosions kind of boring and low-tech if you can accelerate shit to relativistic velocities?
>nuclear explosions
E = mc^2
>accelerate shit to relativistic velocities
Ek = 0.5mv^2
At best you can approach half of the energy.
That said, the famous mass-energy equivalence formula doesn't really apply to nuclear reactions despite often used in that context. Only to matter-antimatter annihilations.
You forget that shit stops being classical after a few percentages of the speed of light, and at that point become more relativistic instead
Weird things happen when time seems more like a suggestion and the concept of simultaneous events doesn't exist anymore
If you accelerate a single hydrogen atom close enough to the speed of light, you'll eventually end up with a black hole
I really didn't want to try writing the relativistic part on PrepHole.
And it doesn't differ from the classical part much before you get into ridiculously high fractions of c, over 60%
Goddamn PrepHoleX fricked up the PNG
>Ek = 0.5mv^2
That's the non-relativistic part of the equation. At silly enough velocities it is dwarfed by the relativistic part; as the object's velocity approaches c the energy approaches infinity.
That said, I'm not sure what's scarier, a tiny particle flying at a fraction of the speed of light, or the machine that performed the acceleration (presumably with less than 100% efficiency).
Go back to school
300 km/s are by no means a 'Relativistic' velocity.
No, but "percentages of the speed of light" are kind of getting there.
Although another tradeoff is that really small ones tend to require more exotics to get much bang which means their shelf life is lower and they need refurbishment more often. A super basic full size gun type would be good for decades if not a century, to some extent limited by the high explosives, just sitting untouched some cool/dry. The yield for the heaviness is kind of shit tho. The smaller and more efficient the more upkeep in general. A rifle launched grenade maybe could go far enough to avoid killing the operator 100% of the time in principle but if it needed to be rebuilt every few years the logistics would be impossible.
Pretty much anon
https://en.m.wikipedia.org/wiki/Davy_Crockett_(nuclear_device)
You can have a nuclear explosion by firing a 50 gram paraffine slug at 300 km/s against any organic target
Yes they are theoretically possible but way beyond any capability we possess even in the somewhat distant future. Nuclear fission reactions are basically an issue of probability, the higher the probability of neutrons hitting enriched uranium, the greater the chance it will result in a chain reaction and a full nuclear explosion. Nukes utilize neutron reflectors to achieve critical mass without necessarily requiring the textbook amount, these reflectors will increase the probability neutrons will bounce around and hit u235 atoms, thereby reducing the overall uranium required to achieve a nuclear blast. Suppose we somehow manage to find a material that can perfectly reflect all neutrons it comes into contact with, then a bullet sized u235 sample shrouded by that reflector, and imparted with a free neutrons would certainly cause a nuclear explosion.
>are nuclear rifle rounds theoretically possible?
Oh boy they're not just possible (though it's not a normal rifle but a large recoilless smoothbore) the mad men built them. 20 ton TNT equivalent nuclear devices launched a whole 1.25 to 2.5 miles away.
https://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device)
>with a 100% instant casualty radius in excess of 160 metres (520 ft). The shell's greatest effect would have been its extreme prompt neutron radiation which would have killed most of the enemy troops inside that circle within minutes. Its blast would do very little if any damage to the enemy's tracked vehicles. Troops further away would have died within hours, days and less than two weeks depending on their range from the point of burst and the thickness of their protection.
this time period in american history was pretty fricking insane because the nuclear deterrent strategy was basically being so insane that the soviets wouldn't even try to play ball. the problem is that the soviets were probably the only people crazier than the trilateral commision
the general idea was that a full scale war would devolve into the soviets suicide zerg rushing the continental US with hundreds long range strategic bombers packed to the brim with nukes and this was like 20 years before they had even invented guided missiles let alone avionics packages and radar systems, the solution to that was to nuke them in the air and there was only one plane big enough to do that
the b-58 huslter being basically the dumbest plane ever built because it sacrificed everything to go vaguely fast in a straight line to shoot one nuclear bottle rocket and was obsolete within like five years because they figured out how to guide missiles
Our species will always amuse me with how we can make the dumbest shit that still technically works, sure in a hyper specific scenario, but there you are. What, you want to dunk on the Russians using a NUCLEAR POWERED ramjet? Project Pluto. A(probably) function plasma weapon that’s really only useful in space? MARAUDER. The US MIC are wizards and no one can convince me otherwise
>A(probably) function plasma weapon that’s really only useful in space? MARAUDER
Wrong. The smoke ring principle of stabilization used by MARAUDER only works in an atmosphere. In space you want a nuclear shaped charge if you're going to shoot plasma for offensive purposes.
A nuclear salt water rocket, if proven to work, could perhaps be repurposed as a multiple-use nuclear plasma cannon in space. It'll still be short ranged because the charged plasma particles will repel each other unless you manage to neutralize them first, so a shaped charge nuke warhead on your torpedoes make more sense.
Man, I love and miss the pod-style engines.
TAKE ME BACK
>I wasn't even born then.
>that pic
Rock hard for peak 50s aesthetics
>are nuclear rifle rounds theoretically possible?
try anti matter warheads
According to the internet. In the 50s, suitcase bomb development created a roughly 5 inch implosion device and detonated to create .19kt or 190 tons of tnt. However with the amount of primary explosive necessary to facilitate a nuclear reaction the suitcase still weighed roughly 100 pounds.
https://en.m.wikipedia.org/wiki/Davy_Crockett_(nuclear_device)
The mini nuke davy Crockett was smaller still. And generated a .02kt or 20 ton explosion and still weighed 75ish pounds with its primary explosive and propellant. But it's about as small as they've made them. You could possibly get even smaller if you just use some high speed mass driver to assist in getting the chain reaction underway. But then you'd be dealing with a large shooty
don't think there's enough in a bullet to go critical. you can actually look this up in radiation charts based on the distingrations