What round can stop a car?

[TraditionalCatholic]

Unless you take out the driver, not much is going to stop a car immediately, short of high explosives or extremely large AP rounds. Going through an engine block isn't that difficult, but a hole in a block isn't going to stop the engine, and, even if it does, it won't do this immediately.

 

[gym]

If you hit him in the head he will just let off the gas. He may coast a while but by then you could shoot enough other stuff that it would stop, or you could walk up and turn the ignition off. Let me know how you made out, lol

 

[lemaymiami]

There's one other thing about force of any kind applied to a moving car that I didn't mention, but remembered later. In police work you learn the hard way about unintended consequences of one action or other. It was carefully pointed out to the folks that ran my Department some years ago that whatever intervention you cause to a moving vehicle you're very likely to own whatever the end result is.... That sort of stuff is a lawyer's dream come true. The way we dealt with it in chases was simply to keep after them until they crashed without any help from us. None of that P.I.T. maneuver stuff under any circumstances (since anything that happpens after you ram another car is your responsibility in civil court - at least in south Florida...). Every shooting into an occupied vehicle that I know of was problematic in one way or another. The only way any of them was ever justified was when an officer was clearly defending him(or her) self. We even made a point of in our procedures that an officer on foot should never place himself in the path of a moving vehicle (in other words causing the "self defense" moment).

Every police outfit has its wild and crazy moments, occasionally with some young officer really risking life and limb to make an apprehension. In the real world you give them a medal and an 'attaboy'. If they do it twice you find them another job assignment, usually as far from the street as possible (not like the movies at all....).

And so it goes...

 

[Keauxbi]

I once heard that the desert eagle was designed to punch holes in engine blocks for Israeli border patrol.
Sad to see how little people know about cars. Most cars are very easy to "stop", but stop is a very vague term. Stop the engine? Take out the computer sure. A shot through the battery could do that as well. Put a hole in the oil pan and eventually a dry engine will seize, same with an automatic transmission oil pan. Someone said that an auto-tranny will keep on going, but the engine spins the torque converter, without the engine spinning, then the car's momentum will run out.

 

[kingpin008]

If you hit him in the head he will just let off the gas.

Maybe, maybe not. In reality, the brain causes all sorts of wacky crap to happen when it takes a serious lick. Ever seen a MMA fighter hit the ground and stiffen up after a really vicious knockout? That's the brain reacting to trauma. Same thing is possible with other forms of trauma, including gunshots. While a headshot will likely cause catastrophic loss of motor control, I wouldn't rely on absolute statements like that.

 

[Frozen North]

It is like Luke Skywalker blowing up the death star.... You need to use the force!

Seriously, if you are able to stop a speeding car with a small arm, it is pure luck.

I have several LEOs, paramedics, and fire fighters among my close friends and family. They will all tell you that they have seen horrific car crashes with the vehicles damaged beyond recognition. Many of these cars will still be running when they get there to tend to the victims.

I had a Ford F-150 as a kid. It had a really worn out (really really worn out) 300 inline 6 cylinder. We drained the oil and water to swap engines and my buddy had an idea. We started it up to see how long it would go with no fluids before it locked up... 8 minutes it ran dry as a bone. It finally just lost rpms and stopped, nothing dramatic.

You need a large belt fed weapon at least, or allot of luck!

 

[Erik M]

puncture the transmission pan, oil pan, or radiator. It will stop eventually. Even a 17 hmr could do that. If enougn rounds of a high caliber weapon could be dumped into the engine bay eventually you are going to diable a critical component, ie ECM, Fuel Rail, Fuel Injactor, Distributor. . . Commandeer an A10 and unleash the GAU-8. Im pretty sure the Warthog is the answer to any and all of these questions.

 

[788Ham]

Put an 150 gr. .300 Savage dead center in the grill, that'll smash enough things up to stop it in short order! Bust up the water pump, it ain't going very far then.

 

[Strykervet]

I have a .50 Beowulf upper that we tested in the army for just this purpose. We wanted something for roadblocks when a Stryker wasn't available or feasible. Never tried one on an actual running vehicle, and the unit decided that despite the performance, they didn't want to go that route. I thought they would have been nice to keep an upper in each Stryker though for just this reason. As a side note, the .500 S&W is similar in ballistics and would probably do a similar job provided it has a long barrel.

The Coast Guard did go with it, and I saw something on History Channel or some such where they were firing it from a helicopter at outboard engines. They used a Barrett too, which would work much better as that is what it was made for, disabling light vehicles.

The problem is that when you shoot to disable the vehicle, you really got to put several rounds in there and then wait until the engine overheats, unless you get a lucky shot.

At any rate, you want a heavy bullet to stop a car since cast iron is very hard and will shatter or crack. You won't find much in the way of shoulder fired weapons that can penetrate one short of the BMG. If you can hit the intake sufficiently hard enough to make it lose vacuum, it will roll to a stop faster.

My buddy had to stop a car in Iraq that ran a roadblock. He used the RWS on the Stryker, a remote controlled .50 BMG. Now that stopped it, sort of, it still had to roll to a stop. Besides smoking the driver and passenger, the hood exploded in sparks and shrapnel and the whole thing was a burning smoking mess in less than a minute. That was with Raufoss HEAP ammo though.

 

[MachIVshooter]

As a retired automotive engineer, I can attest to the current thin walls in modern lightweight cast engine blocks, and that they are NOT designed to resist any sort of penetration. They only hold the head up, and contain the coolant and the various reciprocating bits! So, perhaps a .357, esp,. a heavy jacketed bullet, might well penetrate the block, and then connect with an equally unarmored piston, and let the coolant and/or oil and or/high-pressure fuel, "out", and thus might eventually shut'r down by "mass internal corruption".

Breaking out the water jacket is one thing; Penetrating the steel lined cylinder is quite another.

It would seem if the ecm could be reliably located, it wouldn't take as much power as what would still the engine. I have 2 Fords with ecm's in the same general areas.

They can be just about anywhere, often inside the passenger compartment (Asian). Many domestics are contained inside the air filter housing to facilitate better cooling (No, they cant be accessed just by removing the filter). VAG puts them under the windshield cowl.

Shoot for right behind the driver's side headlight, from the side. That's where the TCM (transmission control module) is for most cars (between fender and battery).

In most cars, the TCM is integral with the PCM, and they're rarely located behind the headlamp. To my recollection, only Chrysler put the PCM there from 84-93 on TBI and MPI cars and trucks and '91-'01 Jeep XJ. On Turbo cars, it was the power module; The actual PCM is behind the passenger kickpanel. '87-'90 Renix Jeeps did have a separate TCM, but it lives behind the glovebox.

Regardless, trying to hit the PCM from outside the vehicle is like trying to do a 14 ball combo and sink the 8 on the break. Even if you know where it is, in most cases, actually hitting that relatively small component (largest in GM's, still only about 7x9x2")through everything else would be extremely difficult.

I work on all makes and models, 14 years doing heavy line and diagnostic. I still have to look up PCM location quite frequently when doing pin-out and continuity tests for driveability diagnostics.

ETA:

If you guys wanna test your thinking on this stuff, throw out a year and model, tell me what you want to hit. I'll tell you where you'd have to aim and what you'd have to get through first.

 

[Ole Coot]

Several years back I do know of a few diesel coal trucks that were stopped by regular 30-06 in Eastern KY during a strike. Where they hit, distance etc I don't know. I only know what was reported and I wouldn't tell one of those men it can't be done either. All were shots to the motor.

 

[JustinJ]

How about an incendiary round to the gas tank? If its low enough on fuel and has the right air/fuel mixture the tank should explode.

 

[ForumSurfer]

IMO, rather than stopping a car, it's best to just not ever pick a fight with one.

Best advice yet.

 

[M-Cameron]

How about an incendiary round to the gas tank? If its low enough on fuel and has the right air/fuel mixture the tank should explode.

.....except for the fact that, the two nice hole you punched in the tank with the bullet is also going to nicely vent any pressure built up by the burning gas.....thus, no BOOM.

 

[JustinJ]

".....except for the fact that, the two nice hole you punched in the tank with the bullet is also going to nicely vent any pressure built up by the burning gas.....thus, no BOOM."

It's not the pressure that would cause the boom but the fuel/air mixture. Either way though ignition would occur before any change in pressure could occur. In WWII Japanese Zero fighter plane fuel tanks had no bladder so as fuel was used air would enter the tank and mix with vapors from the fuel. Because of this they were prone to go up like a roman candle when the tanks were hit. American fighter planes, or at least some models, had rubber bladders in their tanks that shrunk as fuel was used to prevent this.

 

[M-Cameron]

It's not the pressure that would cause the boom but the fuel/air mixture. Either way though ignition would occur before any change in pressure could occur. In WWII Japanese Zero fighter plane fuel tanks had no bladder so as fuel was used air would enter the tank and mix with vapors from the fuel. Because of this they were prone to go up like a roman candle when the tanks were hit. American fighter planes, or at least some models, had rubber bladders in their tanks that shrunk as fuel was used to prevent this.

in just about every low explosive......its the buildup of pressure that causes the boom, thats the basic principle of how explosives work............otherwise its just burning

take a coffee can, spray some hairspray in it......keep the lid off.........and light it......itll burn, but it wont explode..

repeat the same situation, put the lid on, and light it.....BOOM....the lid will go shooting off.

 

[shootingthebreeze]

Why?

 

[Tirod]

To stop a moving car takes an equal force moving in the opposite direction.

4,000 pound car moving at 45mph - shoot another 4,000 pound object at it with velocity at 45mph.

What gun does that? Nothing any human could use as a single operator weapon that can be carried.

It's a silly question for those who slept thru high school physics. As any shooter should be aware, for any force there is an equal but opposite reaction. In this case, it takes an equal but opposite force to create a complete dead stop.

 

[M-Cameron]

To stop a moving car takes an equal force moving in the opposite direction.

4,000 pound car moving at 45mph - shoot another 4,000 pound object at it with velocity at 45mph.

What gun does that? Nothing any human could use as a single operator weapon that can be carried.

It's a silly question for those who slept thru high school physics. As any shooter should be aware, for any force there is an equal but opposite reaction. In this case, it takes an equal but opposite force to create a complete dead stop.

if you want the car to stop INSTANTLY!...technically yes.....

if you want the car to stop within the next say 100 feet....as in within the spirit of OPs question...no.

 

[MMCSRET]

If and when you identify a round that can just set the park brake and move the selector lever to Park without doing any damage, please let all of us know!!!!!!!!!!

 

[JustinJ]

"in just about every low explosive......its the buildup of pressure that causes the boom, thats the basic principle of how explosives work"

The pressure you are reffering to is caused by rapid expansion and release of gasses through combustion or some other chemical reaction. Two small holes from a gun shot will have no chance of relieving the pressure caused by ignition of gas vapors in a fuel tank fast enough to avoid an explosion. Plus, not all explosions fall under the category of low or high order. A cloud of combustive gasses does not need to be inside of a container to explode as is seen by a fuel/air bomb. The only thing needed for such an explosion is the proper mixture of fuel and air and then an ignition source.

 

[Havegunjoe]

Shoot the driver and don't worry about the engin block.

 

[gym]

I got it, an EMP, that can be aimed at his engine, like the one they used in oceans 11 only smaller. It should just short out the electrical system and with no power the car should stop. But don't they already have those? they seem to be dangerous because the car is going to gradualy slow down unless it hit's something. They tried them from helicopters I believe. I wouldn't want to be in the helicopter. Or an RPG if you weren't worried about collateral damage or survivors. How bad do you want to stop this car?
For a speeding ticket these are all bad ideas. Maybe a paint ball gun, so they couldnt see.

 

[JustinJ]

"It should just short out the electrical system and with no power the car should stop. But don't they already have those? they seem to be dangerous because the car is going to gradualy slow down unless it hit's something. "

I believe they've created devices that can be slid under a car or placed for the car to driver over that will cause the electrical system to fail via en EMP. I can't imagine that being more dangerous than tire spikes.

 

[Panzercat]

They were also experimenting with bumper mounted lances that would discharge into the fleeing car's frame. The pursuing car would litterally ram them to make contact.