Oops.

I did, indeed, overlook that rather important fact. Thanks for catching my error!

(I had to step out of the room in the middle of the ballistic gel shot, and only saw the results. I forgot that they had been setting it up point-blank.)

I live less than two miles from the original steam gun, currently on the side of US Route 1 in Elkridge, MD. The gun was operational and was fired during the Bicentenniel. It looks exactly like the old wood-carvings shown during the episode.

quote:

Originally posted by BattlingDragon:
I live less than two miles from the original steam gun, currently on the side of US Route 1 in Elkridge, MD. The gun was operational and was fired during the Bicentenniel. It looks exactly like the old wood-carvings shown during the episode.

How long before you can get pictures? I would like to see it.

The ballistics gel vs pig thing is a moot point.

Mythbusters finally realized that they needed to use more than ballistics gel for their experiments some time ago.

Ballistics gel is great... for seeing how far bullets will penetrate and what they do. For most everything else, the guy may as well have been made out of jello. The human body has many things in it that don't act like gelatin. Bones, tendons, muscles, etc.

I often cringed at the assumptions the MB's were making by using only the ballistics gel for their results.

BTW, the mysterious noise that baffled Jamie & Adam is actually quite common. It comes from the heating elements. Probably 20% of all new electric water heaters (or replacement elements) will make that sound when they are first installed and powered up. After one or two heating cycles it will go away. It is due to the natural frequency of the element, some tend to mimic a tuning fork when current is ran through them.

the problem was the timing, if the timing was correct then it would be lethal. instead these balls just rolled down then they came out

in the pirate myths, i know its hard to hold the boat down in the water.....but i heard the native americans would use that method to sneak up on their enemies......so is it true?

quote:

Originally posted by funkeymonkey07:
in the pirate myths, i know its hard to hold the boat down in the water.....but i heard the native americans would use that method to sneak up on their enemies......so is it true?

Wrong episode discussion board

Centrifugal Force

Presumably Jaime and Adam have a decent idea of the failure point of their water heaters from the previous tests which is why they used them again. Presumably they didn't have them too close to the failure point.

What I would like is more information about just how they decided what specs to use. Was the 2000 rpm accurate? Or was it a guesstimate from the patent application? I'm not sure how well they could measure the rpm during the War Between the States, and the final results might have been a higher rotational speed, and hence higher velocity.

I'd also like to know just what results they got. What was the muzzle velocity? Some crude calculations based on the "700 yards at 20 degrees" shot say it was about 330 feet per second. This assumes that the round flew 700 yards and then stopped dead when it hit, which I suspect is rather unlikely.

The device they built also seemed smaller than the illustrations of the original I've seen. Theirs looked to be about 2' or maybe 2 1/2' in diameter. The original appeared to be closer to 6' or so. Triple the diameter would be triple the velocity, assuming the same rotational speed. If this model had a mv of 330 fps, a larger device could have produced near-supersonic projectiles, or close to the same velocity produced by the period rifled musket used for comparison.

All in all, looks like a revisit will be needed.

quote:

Originally posted by for24:

quote:

Originally posted by BattlingDragon:
I live less than two miles from the original steam gun, currently on the side of US Route 1 in Elkridge, MD. The gun was operational and was fired during the Bicentenniel. It looks exactly like the old wood-carvings shown during the episode.

How long before you can get pictures? I would like to see it.

From what I've been reading, that's a reproduction, and the original was scrapped around 1900.

http://www.baltimoresun.com/entertainment/tv/bal-to.myt...0,2900119,full.story

"While there are no remnants of the old steam gun to be found, what appears to be a replica of it sits in Elkridge, behind the Elk Ridge Landing marker along U.S. 1. The paint-chipped, weather-beaten contraption sits amid tall grass. It looks like Dickinson's gun, but it has no signs or markers."

Also, according to Union Brigadier Benjamen F. Butler, who captured the original, it was operational at that time. No comment was made about it's effectiveness.

"I have also the honor to communicate the capture of the steam gun, and the fact that I have found men in the Sixth Massachusetts Regiment who have been able to put it in operation, and it is now in full working order."

http://www.civilwarhome.com/Baltimore6.htm

quote:

Originally posted by jandrese:
Centrifugal Force

Presumably Jaime and Adam have a decent idea of the failure point of their water heaters...

From how they were acting concerning the noises and fear on shutting it off when it malfunctioned, I would say that they DIDN'T. They were just hoping that everything would hold together, with full knowledge of what would happen if they did not. Even their plumbing looked to be suspect, not the Schedule 80 fixtures that one would expect.

This myth needs a revisit, but with much more attention paid to doing it right

They had two safety pop-off valves incorporated in their piping system which presumably had a rating well below 350 psi.

I am glad to see two others have pointed out the egregious use of centrifugal force 2 or 3 times in the episode. The first time I heard the word centrifugal come from the voice-over guy I had to backtrack my Tivo and make sure I heard correctly. Then I yelled at my TV. They further compounded the error by showing arrows meant to represent the force on the projectiles all pointing toward the outside of the circle. I actually had one of my physics students come in the morning after the show commenting about it. Please check your science content before you put it on the air. I know it can be hard to fully explain circular motion quickly (an outward force on an object undergoing circular motion is a common misconception) but airing "bad science" just helps to perpetuate the misconception.

What kind of bullets did they use? It looked more like rubber balls than steel..

I live in Elkridge, Maryland and i see the cannon and the place where it was captured. I think it is lethal for shooting that far. Their is probaly a diffrence diseign. The fear factor is probaly more important. Also the design is made not to just be acurate but is made to shoot rapidly every thing around it and not one person. It has 180 degress of turn for the gun to turn aroun and destroy an attack around it. Also they should use a more lethal ball like the one's in the civil war.I give it a possible that it was a lethal and a great wepon.

I love the complaints about the use of Centrifugal force.

As much as some physics <teachers> might want to deny it, it does "exist".

http://en.wikipedia.org/wiki/Centrifugal_force

"As a result, even students who master the physics curriculum may leave school with the false impression that it is never scientifically valid to speak about centrifugal forces."

Heh... Those who cannot do... teach.

pictures of the replica in Maryland: http://www.flickr.com/photos/21701734@N04/sets/72157603418171995/

quote:

Originally posted by ericw66:
Using lead or steel balls would have not changed the results much. They'd have been moving slower, and the penetration (if any) would have been reduced by the loss in speed to about the same as those plastic balls (if that's what they were).

If they'd used it in the civil war, it wouldn't have been a field of wounded men. It'd have been a field of irritated men with welts (unless unlucky enough to be hit in the eye of course).

The lighter something is, the easier it is to accelerate it to a high speed.

Energy = ½ x Mass x Velocity2
or
Energy (ftlbs) = [(Velocity (fps))2 x Weight (grains)] ÷ 450,240


But it is not how much kinetic energy a bullet has, it is how it puts it to use.
And it is not how much energy the projectile has at the muzzle but how much it has at the target that is essential.
The same property that lets a light projectile accelerate more also means that it can be more easily slowed by the air it is passing through.
A heavy pellet may have less energy at the muzzle, but it’ll have a greater proportion of this energy by the time that it reaches the target.
Remember cigarette butt and silver bullets do less damage than the normal did

That being said I didn’t think they used plastic but painted metal pellets

Looked like rubber pellets to me...
And anyone who has been hit by a rubber bullet, can tell that they aren't lethal at a distance. But they do pack a punch and hurt like hell (which is their purpose, Rubber bullets are often used to disperse a crowd.. Like bean bags, Mace or Water cannons)