# Explain the whole bullet and train thing to me.
**URL:** https://boards.straightdope.com/t/explain-the-whole-bullet-and-train-thing-to-me/384642
**Category:** Factual Questions
**Created:** [December 18, 2006, 4:07pm UTC](https://boards.straightdope.com/t/explain-the-whole-bullet-and-train-thing-to-me/384642 "2006-12-18T16:07:35Z")
**Posts on this page:** 7
**Page:** 3
### Author:  [@Princhester](https://boards.straightdope.com/u/Princhester)
#### Post date: [December 7, 2022, 3:16am UTC](https://boards.straightdope.com/t/explain-the-whole-bullet-and-train-thing-to-me/384642/41 "2022-12-07T03:16:49Z")
I think it’s very cool that I said to QED who was (at around that time) working as a researcher on Mythbusters that this would make a cool episode, and then they did that episode. I’d forgotten about this entirely till this zombie was raised from the dead.
From now on I’m going to tell people I may have been the person responsible for this episode. Is it true? I don’t know. I don’t think QED was in the job long. But the story is too good not to tell 🙂
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### Author:  [@Princhester](https://boards.straightdope.com/u/Princhester)
#### Post date: [December 7, 2022, 3:18am UTC](https://boards.straightdope.com/t/explain-the-whole-bullet-and-train-thing-to-me/384642/42 "2022-12-07T03:18:02Z")
… which is why record setting land vehicles can’t have rubber tyres - the accelerations involved would tear them apart.
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### Author:  [@mixdenny](https://boards.straightdope.com/u/mixdenny)
#### Post date: [December 7, 2022, 6:37am UTC](https://boards.straightdope.com/t/explain-the-whole-bullet-and-train-thing-to-me/384642/43 "2022-12-07T06:37:46Z")
A related fact is that you never rev your stationary car in top gear if only one drive wheel is off the ground. Due to the differential action if you accelerate to 100 mph the tire is going twice that. 200 mph. BOOM!
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### Author:  [@WhyKickAMooCow](https://boards.straightdope.com/u/WhyKickAMooCow)
#### Post date: [December 7, 2022, 12:34pm UTC](https://boards.straightdope.com/t/explain-the-whole-bullet-and-train-thing-to-me/384642/44 "2022-12-07T12:34:18Z")
Easily demonstrated with R/C vehicles!
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### Author:  [@Loggins](https://boards.straightdope.com/u/Loggins)
#### Post date: [December 7, 2022, 8:29pm UTC](https://boards.straightdope.com/t/explain-the-whole-bullet-and-train-thing-to-me/384642/45 "2022-12-07T20:29:54Z")
Bare with me now, and i only read half of the thread before getting antsy. So i Travel at 1000mph, and fire a bullet backwards, but lets say the bullet speed was max 500mph. Would that bullet follow the train and kill anyone it hit that came in the way?
So shooting it backwards at half speed of your 1000mph train, would still give it a forward speed of 500mph?
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### Author:  [@Chronos](https://boards.straightdope.com/u/Chronos)
#### Post date: [December 7, 2022, 10:39pm UTC](https://boards.straightdope.com/t/explain-the-whole-bullet-and-train-thing-to-me/384642/46 "2022-12-07T22:39:04Z")
Yes, correct. And if someone somehow managed to miss the train but still get in front of the bullet, it’d do the same thing a 500 MPH bullet normally would. There might be some slight differences in the wound due to it entering the target back end first, but I don’t imagine the overall effect would be much different.
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### Author:  [@mixdenny](https://boards.straightdope.com/u/mixdenny)
#### Post date: [December 8, 2022, 12:47am UTC](https://boards.straightdope.com/t/explain-the-whole-bullet-and-train-thing-to-me/384642/47 "2022-12-08T00:47:00Z")
> [@Q.E.D](#):
>
> On the other hand, you might not want to catch it barehanded. Remember that although the bullet has no linear velocity in parallel to the ground, it still has a large amount of rotational energy–it’s spinning at several tens of thousands of RPM. It would be like trying to catch a drill bit.
This brings up something i find interesting. Let’s take reasonable bullet and barrel specs using easy to understand SAE units to make the math simple. (Ducking as the Metric guys throw tape measures at me).
Barrel twist rate = 1 turn in 12". Bullet velocity = 2400 fps. This gives us 2400 rps or 144,000 rpm. You now get shot in your 6" thick thigh. Yeah, the bullet is spinning at 144,000 rpm but it only makes one half of a revolution as it passes through your leg. One half of a twist. It isn’t like a drill bit spinning for a long time in one spot. Now _ **catching** _ it would be different - you just grabbed a spinning hornet. It’s pretty awesome looking:
> **[Video: Bullet Spins On Ice After Shooting Frozen Lake | OutdoorHub](https://www.outdoorhub.com/news/2018/12/07/video-bullet-spins-ice-shooting-frozen-lake/)**
>
> once he fires, the person filming quickly picks up on it and zooms in as the bullet spins on ice underneath their feet.
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