Is it possible to have nuclear bullets?

Question

I was just wondering whether it would be possible to arm soldiers with bullets tipped with tiny nuclear warheads that could be devastating in combat...or would the action of striking the bullet set off the warhead as well and harm the user? Sounds a bit quirky i know but im curious nonetheless.

Answer 1

Nuclear explosions aren't set off by force, so shooting would not set it off.  However, the small amount of uranium wouldn't do anything in an explosion, and putting such complicated small devices on bullets would make them unable to be mass produced.

Answer 2

The bullets would probably be too small to provide a sufficient nuclear explosion.  And it would be fairly volatile, so could pose a danger to someone carrying the bullets around.

They do use depleted uranium in armour piercing rounds, but that has most of its radioactivity used up.

Answer 3

Would you want to put even a limited nuclear arsenal in the hands of an 18 year old public school graduate?  Think about it...

They already use spent plutonium bullets which are still radiating...

Answer 4

No.

To get a nuclear explosion you need enough fissile material to cause a chain reaction. Fissile material is uranium, plutonium or any other weapons grade radioactive material.

As an atom splits, it releases two neutrons, which hit another tow atoms, which split, releasing four neutrons, etc etc. When such a split occurs in the middle of the material, the neutrons are very likely to hit an atom, but when a plit happens on the outside, the neutron is lost.

There are two ways of getting a nuclear blast. One is getting a piece of fissile material large enough so that most atom splits happen in the middle, the other is to reflect neutrons back.

Traditional nuclear bombs, such as used in WW2, used two pieces of material, which were slammed together so a chain reaction could form. This is known as Critical Mass. This requires several pounds of nuclear material, and several tonnes of metal shielding if you plan on living through using it.

Modern nuclear weapons use a neutron relfector, which is a material that reflects most neutrons back to the material, so that a chain reaction can occur even without critical mass. They also use an explosion to compress the fissile material to improve the odds of a neutron hitting an atom, causing a chain reaction. This way, you only need a few hundred grams of material, and a few pounds of shielding.

However, the smallest true nuclear weapons are still the size of a large basketball (see imagine in source), known as the Davey Crocket. This is generally thought to be the smallest possible nuclear weapon.

It is theoretically possible to make smaller nuclear weapons, but it would require using different materials, that are far more radioactive than uranium. These materials also decay faster, so they would only have a short shelf-life. The problem becomes one of scale. At a certain point, you need so much non-explosive stuff, that it becomes more effective to just use regular lead. A dozen 12 cent lead bullets are just as lethal as a theoretical $ 20.000 nuclear bullet.

fun fact: At it's highest yield, the lethal radius of the Davey crocket rifle was larger than it's fire range.....  

Answer 5

Current state of technology, No.  Can't get Critical Mass in that small a package.  Best we can do is about 60 pound backpack.