Bullet Stability...spontaneous combustion?

[Blarneystone]

Sorry if this question has been asked a million times, I tried searching but could not find it.

My question is: How stable is the average bullet? I've got a bit of a phobia about compressed gasses and gunpowder, so I am curious what elements could affect a bullet and make it explode. I am not the only one...a buddy of mine was asking me too.

Would keeping it in your glove compartment on a 100degree day cause any problems?

Would throwing it into a fire cause the bullet to fire out randomly?

How about if you had a handful of bullets and threw them down on the pavement as hard as you can...?

I know some of these questions are ridiculous...but I'd like to know how stable they are. I handle them pretty darn carefully as is.

At least I didn't ask what would happen if you put one in the microwave! It would explode..right?!?! :p :p :p

[dischord]

Explode? Perhaps in some situations. But the fact that the ammo is not in a barrel means the likelihood of this causing a dangerous projectile is low.

It's the barrel that creates the velocity. All the energy from the explosion -- being blocked from behind and all sides -- is channelled toward the open end of the barrel, pushing the bullet in front of it. Without the barrel, much less velocity, if any

Didn't American Rifleman run an article about this a few years ago? I remember photos of ammo, the bullets still in the casing, with the sides of the brass blown out. The explosions took the path of least resistance, which seems to be the casing sides rather than the bullets themselves.

Having said that, I wouldn't play around -- throwing bullets into fires and all. There's no sense in risking it, no matter what the odds.

[nine fingers]

Would throwing it into a fire cause the bullet to fire out randomly?

Didn't American Rifleman run an article about this a few years ago?
Yes, they did and I remember it well. The tests were done by a fireman, to see what danger a firefighter was in during a fire where ammunition was stored. He determined that the most likely thing to happen was for the primer to blowout. This could cause some very minor injury to bare skin or more severe if hit in the eye. Firemen, however, would not even notice it through their protective clothing.

Would keeping it in your glove compartment on a 100degree day cause any problems?
As for keeping ammon in hot locations, the flash point of modern powder is well above 100, but, why do it if you don't have to?

How about if you had a handful of bullets and threw them down on the pavement as hard as you can...?
Sure, if something hit the primer just right, but the result would be similar to the fire situation. But at the cost of good ammo today, I'd rather use a gun.

[Mike Irwin]

That article would have run around 1994, either just before or just after I left American Rifleman.

The author was, I believe, Gary Siuchetti.

I don't think he was a fireman, but he got a fireman's turnout coat to use as part of the testing process.

Generally the most dangerous part of the "popping" shell is the primer cup. It can fly out at high velocity and, at short range, could cause a serious injury especially if it hit you in the eye.

There was, in fact, an "In My Experience" in Rifleman a couple of years earlier that recounted a man's experience such an event.

I can't remember it entirely, but for some reason he was heating a primed, but unloaded, case with a torch, and the primer popped. The primer cup ended up going between two ribs and lodging in his lung.

[Mal H]

Blarneystone - While we're at it, I thought you might appreciate a very small lesson on the nomenclature of ammunition.

A bullet is only the projectile that is held fast in the mouth of a case. Together, along with the primer, they form a cartridge (or round). So your questions all have to do with cartridges rather than bullets.

As for putting a cartridge in a microwave oven, intuitively I don't think it will explode since the cartridge is a completely closed system made of ungrounded metal. The microwaves should bounce off the cartridge and dissipate just as they do on the inner metallic walls of the oven. There is a chance that some heating will occur in the imperfections on the surface of the cartridge which could cause it to go off, who knows. I'm sure not going to test my theory however. :) I'm not sure but I think that if the metal is smaller than the wavelength of the microwave however, the energy is absorbed and heat is generated. (Like placing steel wool in a mic. oven.)

[k77/22rp]

A bullet is only the projectile that is held fast in the mouth of a case. Together, along with the primer, they form a cartridge (or round). So your questions all have to do with cartridges rather than bullets.

I was waiting for someone to say something, Icant stand when someone calls a cartridge a "bullet" just like wehn someone calls a magazine a "clip".

About a month ago I accidently left a couple rounds of .22lr in my pants pocket and forgot to take them out before I washed the pants, they were fine in the washer but one of them exploded in the dryer:eek: I dont know how or why because I have done that before.

Anyone know what could of caused that, is it the heat or would something have to hit the primer

[MAURICE]

can you cut open a shotgun shell without killing your self?
i have been tempted,but i wasnt sure what would happen,so i didnt (probably a smart move)

it seems like you could do it,but i want to be sure.

[Mal H]

Sure, as long as you're careful and don't hit an artery with the blade when it slips. :)

Anyone with an ounce of curiosity and a spare SG shell has cut one open. I believe my first was at age 11 and the most recent one was about a year ago because I wanted to see what bismuth shot looked like.

As always, wear safety glasses. Murphy hates the glare of them and will pay a visit the instant you don't wear them.

[Blarneystone]

My apologies for calling a cartridge a bullet. It won't happen again.

My curiousity surrounds my interest in practicing loading my revolver and trying to improve my speed and confidence. I guess I was a tad paranoid that if I was "slamming" cartridges into the wheel, and dropping them onto the floor, I might risk a minor explosion.

[JohnKSa]

I believe the fire question has been thoroughly covered.

Modern ammunition is not very shock sensitive. It would surprise me to find that dropping or throwing a centerfire cartridge would cause it to fire. If you look at a fired case, you will see that it requires a significant deformation of the primer--you really appreciate this when you see a primer hit by a gun that didn't strike it hard enough to fire it. Still a lot of deformation, but not quite enough to set it off.

Rimfire is another story. A rimfire cartridge thrown against a hard surface could fire if the rim was badly damaged.

Now, what about heat. Ammunition stored in a vehicle will not spontaneously ignite unless the car catches fire. Gasoline is a good bit more volatile than gunpowder if that tells you anything. On the other hand, excessive heat--particularly over time will eventually cause the powder to break down. This weakens the effect of the powder--doesn't cause it to explode or ignite.

The rimfire round in the dryer is interesting--either it got VERY hot, or more likely, a static spark ignited the powder.

When I was a kid, I accidentally left a .22 blank in my pants pocket through a wash/dry cycle with no effect. In fact it was still live after all that abuse--which I discovered in a most unpleasant manner--I still carry a tiny bit of burnt powder around in the white of my right eye to remind me how stupid I was.

[Southla1]

I have probably seen hundreds of rounds dropped in my life and probably half of those were ones that I dropped myself. ONE went off. That happened to a very unlucky airman who was unloading his 38 at the "clearing drum" while in the service. The cartridge hit base first on a rock, and I guess the primer was sensitive. It made a pop like a firecracker but milder. The sad part is that the USAF treated it as an accidental discharge! The airman was not disciplined, but there was an incident reprot written on him, and yes Uncle Sam deducted 6 cents from his next check to pay for the round! Of course he was the squadron screw up too........naturally that did no help.

[PreserveFreedom]

Since the original question seems to have been answered, I'll move on to cutting open a shotgun shell. Many are somewhat transparent. You can usually spot where the paper/cardboard wad is. I prefer to cut on that. You will contain all that shot neatly in one end and the powder in the other if you cut the wad in half. When you get bored with playing with the components, you can use the half with the powder and primer as a blank. Be careful! The wadding can launch with enough force to kill at close range!

[Seeker]

IIRC in the book "Yeager", Chuck relates that he was a bit of a prankster during WWII. One gag he told about was when he walk up to a coal stove were a bunch of other pilots were shootin the breeze, like he had a handdul of coal. It was actually a handful of .50 cal cartridges. He lifeted the lid off dropped in the cartridges, put the lid back on and began to walk away. The other guys figured something was wrong and scrambled. He said the ammom knocked the lid off the stove in a big cloud of soot. He said they didn't much trust him after that.

As an aside I hung with his granson, Jason, a bit in college. Real nice fella = just looking at him it was obvious who his granddad was.

[45King]

One thing that has not been noted in the case of a heat "cook-off" of a cartridge: for most cartridges, the weight of the bullet exceeds the weight of the case. If the cartridge were to cook off, the lighter of the two possible projectiles will be the one to move. It would not move very far, and the velocity achieved would be very low.
In short, if the powder igintes and the cartridge is not contained, the case will push away from the bullet at low velocity.