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Re: spinning bullets on a frozen lake
Posted: Thu Oct 21, 2010 4:26 pm
by Hoi Polloi
7075-T7 wrote:uh oh.... what was seen can not be un-seen.... now I have the strong urge to try this
WildBill wrote:olafpfj wrote:there is no way that this is real. Looks like they're using one of those magnetic stirring systems they use in chemistry labs where you drop the rod in the beaker and put it on the spinning magnet plate.
I'm calling shenanigans!!!!

I don't know how they did it, but I think it's fake. Magnetic stirrers don't work on copper or lead. If the bullet was fired it wouldn't be "pristine." It would have rifling marks on it.
It looks like there are rifling marks on the sides to me.
The first half of page 9 is all about the rifling.
Re: spinning bullets on a frozen lake
Posted: Thu Oct 21, 2010 4:31 pm
by Excaliber
Hoi Polloi wrote:I just read all 9 pages of the MythBusters threads with self-proclaimed experts in physics, special effects/CGI, and firearms chiming in.
There's a lot of tit for tat, things brought up, things explained. Some highlights from the thread which I did not see any refutation of are:
The boy first posted a short video only of a bullet spinning and was told to go out and re-video using certain criteria, which he did and posted just days later (that being the video posted above).
Frame by frame analysis shows that one of the spinning bullets remains in scene 100% of the time, making tampering or editing to create an illusion in this video an extraordinarily time-consuming and expensive venture, much beyond the reach and knowledge of even those beginners in the field of special effects, much less for a teen within a couple days from request to posting. The fact that the camera is hand-held adds to the difficulty in editing in such a circumstance because of the extraordinary skill it would require to line up and merge edited scenes without any discernible signs (such as the bullet being in a slightly different place) when not using a tripod or stationary camera point is far beyond the skill and equipment levels he would be expected to have access to and mastery of.
Several others have duplicated it and posted similar results. Those who shoot regularly posted anecdotes of similar occurrences when they've shot at milk jugs full of frozen water, packed earth, and bowling pins with the fired bullets appearing intact, largely undeformed, and not having penetrated the object. None of them claim historical experiences with the spinning. One person who gives no credentials says it's nothing new to him as they shot the ice and saw spinning bullets all the time growing up.
The big issue of debate seems to be what force would allow its forward momentum to stop while the rotational momentum would continue. Based on the belief that it isn't possible, the primary objection to the video is that it must be a fake because it isn't explained by their basic physics knowledge. I didn't really read those carefully as they don't seem to verify or debunk the video, but to try to explain the science behind what was happening. I didn't see any evidence that the video itself was a fake, though there were many outright statements that people believed it was so.
The poster said that he was talking with the MythBusters staff last January, IIRC, about setting it up and testing it on the show.
I'm no physicist, but this phenomenon doesn't stretch my imagination at all.
Fired bullets are rotating at extremely high speed from their plus or minus 1000 fps trip down a rifled barrel and they're HOT. When the bullet's forward momentum is stopped by the ice, the surface it's in contact with is instantly melted and presents a super lubricated film which would not provide the friction needed to stop the bullet's rotation like sand, wood, or soft dirt would.
I don't have any trouble at all believing that the projectile would continue to spin for a short time until it exhausts its rotational energy in some percentage of shots fired under these conditions.
Re: spinning bullets on a frozen lake
Posted: Thu Oct 21, 2010 4:46 pm
by terryg
Hoi Polloi wrote:Frame by frame analysis shows that one of the spinning bullets remains in scene 100% of the time
If it is the one at around 3:10 or so, it looks to me like the impact was a few (6 to 12) inches above where the 'find' the spinning bullet. It could have been spinning before the shot was fired the camera movements are too jerky to follow directly to the impact spot.
Obviously, I can't know for certain what happened - and maybe this is real. But that is how I can explain the one that 'seems' to stay in the frame the whole time. I think they zoomed in to a different position.
Re: spinning bullets on a frozen lake
Posted: Thu Oct 21, 2010 4:55 pm
by Cobra Medic
I played with enough gyroscopic tops so I think it's theoretically possible under the right conditions but the video is so jerky I'm not sure what I see.
Re: spinning bullets on a frozen lake
Posted: Thu Oct 21, 2010 5:00 pm
by Hoi Polloi
terryg wrote:Hoi Polloi wrote:Frame by frame analysis shows that one of the spinning bullets remains in scene 100% of the time
If it is the one at around 3:10 or so, it looks to me like the impact was a few (6 to 12) inches above where the 'find' the spinning bullet. It could have been spinning before the shot was fired the camera movements are too jerky to follow directly to the impact spot.
Obviously, I can't know for certain what happened - and maybe this is real. But that is how I can explain the one that 'seems' to stay in the frame the whole time. I think they zoomed in to a different position.
Yes, that was the one. It's discussed several times through the thread. Here's the most pivotal conversation point.
Originally posted by jlb002:
I captured frames starting roughly at the 3:10 mark and zipped them up.
frames.zip -
http://www.mediafire.com/?9zr37r7z38kcz07" onclick="window.open(this.href);return false;
Originally posted by rabagley:
Okay, I can see it pretty clearly now. Yup, there's the bullet jumping out of the initial impact point. That means that there is full image continuity in that recording.
Re: spinning bullets on a frozen lake
Posted: Fri Oct 22, 2010 9:53 am
by terryg
Hoi Polloi wrote:terryg wrote:Hoi Polloi wrote:Frame by frame analysis shows that one of the spinning bullets remains in scene 100% of the time
If it is the one at around 3:10 or so, it looks to me like the impact was a few (6 to 12) inches above where the 'find' the spinning bullet. It could have been spinning before the shot was fired the camera movements are too jerky to follow directly to the impact spot.
Obviously, I can't know for certain what happened - and maybe this is real. But that is how I can explain the one that 'seems' to stay in the frame the whole time. I think they zoomed in to a different position.
Yes, that was the one. It's discussed several times through the thread. Here's the most pivotal conversation point.
Originally posted by jlb002:
I captured frames starting roughly at the 3:10 mark and zipped them up.
frames.zip -
http://www.mediafire.com/?9zr37r7z38kcz07" onclick="window.open(this.href);return false;
Originally posted by rabagley:
Okay, I can see it pretty clearly now. Yup, there's the bullet jumping out of the initial impact point. That means that there is full image continuity in that recording.
Ok, frame by frame, that does indeed look pretty convincing. If it is a hoax, these guys are not amateurs. I'll have to give it a Myth Busters 'plausible' at this point.
Re: spinning bullets on a frozen lake
Posted: Fri Oct 22, 2010 3:29 pm
by blackdog8200
Around 2:20, the shooter muzzle sweeps the camera man, right after demonstrating the target shot.....
These are the kind of people that scare me at the range.

Re: spinning bullets on a frozen lake
Posted: Fri Oct 22, 2010 3:44 pm
by olafpfj
AndyC wrote:olafpfj wrote:It could've been carried by an African swallow though.
Supposing two swallows carried it together.
No, they'd have to have it on a line

What? Stowed under the dorsal guiding feathers?
Re: spinning bullets on a frozen lake
Posted: Sat Oct 23, 2010 4:22 pm
by txmatt
Excaliber wrote:
I'm no physicist, but this phenomenon doesn't stretch my imagination at all.
Fired bullets are rotating at extremely high speed from their plus or minus 1000 fps trip down a rifled barrel and they're HOT. When the bullet's forward momentum is stopped by the ice, the surface it's in contact with is instantly melted and presents a super lubricated film which would not provide the friction needed to stop the bullet's rotation like sand, wood, or soft dirt would.
I don't have any trouble at all believing that the projectile would continue to spin for a short time until it exhausts its rotational energy in some percentage of shots fired under these conditions.
That's exactly the explanation I was thinking of. Not so much the heat of the bullet, but the pressure it creates when it contacts the ice and the air between the bullet and the ice right before impact.
Re: spinning bullets on a frozen lake
Posted: Sat Oct 23, 2010 4:38 pm
by GrillKing
It is true. Everything on the Internet is accurate.
Re: spinning bullets on a frozen lake
Posted: Sat Oct 23, 2010 8:13 pm
by apostate
And that's how break dancing was invented.