MythBusters Episode 93: Confederate Steam Gun
Air Date: December 5, 2007
The Confederates successfully created a working steam powered machine gun that could fire bullets using centrifugal force.
busted
The Mythbusters first tried to confirm whether a steam powered machine gun in fact existed. A Civil War weapons expert confirmed that the weapon actually existed and had the blueprints to prove it. However, the gun’s lethality and effectiveness were unconfirmed. They then constructed a steam gun based on the blueprints they received, with a pair of water heaters providing the steam to spin the barrel. On their test run, they fired a single round which struck the gun’s steel safety shield, creating a deep dent which could potentially cause lethal damage to a person. Satisfied with the test run, the Mythbusters took the gun for full scale testing. They tested the gun based on three major factors: a range of 500 yards (460 m), a rate of fire of 400 round per minute, and the fact that the weapon had to be lethal. The gun performed well on the first two criteria, firing five rounds per second at a range of 700 yards (640 m). However, the weapon lacked any lethal force at ranges beyond point blank, and was not very reliable in terms of delivering the bullets to the targets in an effective manner. The Mythbusters concluded that as a concept and a machine, the steam gun performed perfectly, but as a weapon, was too unreliable and impractical.
Through mental or physical means, a person can fool a lie detector test from a polygraph machine.
plausible
In order to make the test results genuine, Tory and Grant were instructed to steal money from a safe while the innocent Kari was used as a control. Also, they were promised a reward (first class seats on the next Mythbusters trip) for beating the test and a punishment (cleaning and waxing the entire crew’s cars) for failing. During the test, Tory attempted to use pain to hide his lying while Grant tried to focus his mind. However, neither of them could beat the polygraph. While they both failed the test, the Build Team decided not to rule out the possibility that there are people out there capable of fooling a polygraph.
A person can fool a lie detector test from an FMRI, which measures brain activity.
plausible
To set up this test, all three Build Team members had to steal something to fulfill the conditions of the myth. Each member had the choice of stealing either a ring or a watch and then underwent a lie detector test while being scanned by the FMRI. Like before, there was a reward ($1000) and a punishment (a trip back to San Francisco via bus; a 3,077-mile (4,952 km) trip) if they passed or failed the test. Both Tory and Kari tried to think happy and fearful thoughts while Grant tried to keep his brain active for the entire test. In the end, Tory and Kari both failed the test while Grant managed to fool the FMRI, making the myth possible.
A person can repair a fuse box by wrapping a burnt-out fuse with tin foil.
confirmed
Adam took some tin foil from a chewing gum wrapper, wrapped it around a burnt-out fuse, and demonstrated that it could indeed work in a fuse box.
(This myth was a promotion for the upcoming MacGyver special.)
Newer: Episode 94: Air Plane Hour
Older: Episode 92: Pirate Special 2
I believe u have purposely not tried the bullet ricochet myth. but if not I would really like to see and know for myself. I think it either pierces or disincarnate not ricochet please respond at least big fan sincerely Waren Boyd
January 21, 2008 at 3:50 AMYour steam gun was not daedly. If you were using rubber balls as bullets that was the problem. You should have gone with metal balls
February 9, 2008 at 7:27 PMThe repairing of a fuse with metal foil is always possible, the problem is that in case of a fault the fuse should be the first thing to burn out to safeguard the circuit. anything metal will do the job including a pin or nail etc. It’s still very dangerous and shouldn’t ever be done.
April 5, 2008 at 6:39 PMYou stated that the gun would not kill. Steam at 40 atmospheres has more power than gunpowder at 500 atmospheres and higher. The design was poor compared to an earlier English Steam Gun.
Jacob Perkins 1824 “Steam Gun”. 300 bullets per minute. Balls of one ounce weight were propelled at 35 yards through an iron plate one-fourth of an inch thick; also through 11 hard planks one inch in thickness placed one inch from each other.
I have the plans and history of this gun if you want to see it and it will kill. There is a problem though of waiting until the steam pressure builds up before you can fire it. In battle you would need instant rapid fire.
May 26, 2008 at 11:31 AMfMRI not FMRI.
August 26, 2008 at 2:15 AMThe problem with this gun was projectile velocity. At 2000 rpms the projectiles only had a velocity of about 250 fps. Most handguns fire at three or more times that. If the barrel was extended a higher velocity would be achieved. The same could be accomplished with higher rpms. Another way to increase lethality would be the use of lead instead of steel shot.
September 28, 2008 at 6:51 PMWe have an electronics kit at home and when the fuse went out, my older brother used a paper clip to bypass it.
October 10, 2008 at 2:25 PMwhile everyone was concentrating on the steam gun, i looked more into the polygraph testing myth. i honestly believe that it kinda fell short.
the mythbusters/buildteam/researchers might have forgotten that there might be (truthfully or mythically) certain professions that are trained to lie and beat the polygraph test by necessity, such as undercover police officers, spies or even the marines. or they could throw in some politicians, telemarketers and used car salesmen. i honestly believe that the episode would’ve been more informative if they tested the polygraph with those types of need-to-lie-to-live professions. it would’ve been really interesting.
also, if they were loyal to their drive in “replicating the results” after a supposed bust, they should’ve tried the polygraph test in its absolute worst case scenario. picture this — if a polygraph test was administered to a person in the outdoors, in a relaxing environment, or in the safety and privacy of their own home, would the polygraph still be able to do its job properly? and how properly? and what happens if you do it to a child? ^_^
mythbusters, i love you guys, but you have to understand that a passed/failed polygraph test is often the difference between guilty/innocent, between job/jobless or between life/death. i’d understand if you won’t want to revisit, but it could’ve been better.
and my sympathies for Kari’s bus ride.T_T
February 9, 2009 at 3:58 AMGuys,
April 18, 2009 at 5:55 PMRead the stuff on the web about control and relevant questions and what to do in each case then let the team practise those principles on a polygraph for a day and then redo the tests.
The reason you Confederate cannon did not work is because the ball was in too loose.You needed to pack the ball tighter so that no steam could escape around the ball which would force the ball out with presure.
May 4, 2009 at 11:27 AMYour cannon did not work because there was not enough seal areound the ball letting the presure out.Barreel has to be packed tight.
May 4, 2009 at 11:29 AMHUGE FAN OF YOUR SHOW!
May 11, 2009 at 11:56 AMI dont agree with busted for the steam powered machine gun because you used rubber maybe if you used metal and it should oh worked. And i think too much steam escaped the barrel.
Penn and Teller claim that the lie detector can be fooled through tightening and releasing the sphincter muscles. However, their “tests” were not as rigorous as Mythbusters’ tests tend to be. Would be interesting for MB to do that test more scientifically.
July 25, 2009 at 10:35 AMBusted for the steam cannon. Not sure. What was the material of the ball? smaller ball could maybe do better penetration. And to people who think about steam in the cannon. guys… there were no steam in the cannon. It was the centrifugal power that throw the ball.. not steam itself. but I really think that a bit smaller ball. and longer barrel could change everything here. double the barrel length and wow…
August 31, 2009 at 10:52 PM