Premier Date: May 27, 2009
Adam and Jamie tested this myth as shown in a viral video (with one galvanized steel bucket full of thermite on top of ten 1-pound/0.45-kilogram blocks of ice). An explosion did indeed occur, thus confirming the myth. Using more thermite and more ice resulted in a larger explosion, enough to literally rain down fire a few seconds afterward and send ice chunks flying over 150 feet (46 m). In a first for the show, however, no explanation was given for why this occurred, because there is none; while hypotheses ranging from the rapid release of hydrogen and oxygen from the vaporizing ice by the thermite to the aerosoling of the thermite itself exist, no one has been able to definitively prove exactly what happens to cause this mixture to be so volatile.
This myth originated from Russian gangs, who use an SKS rifle with a freesliding (as opposed to spring-activated) firing pin. Supposedly, any large vibrations, such as from a loud car stereo system, can cause the firing pin to trigger and fire off round after round at random. To test this, the Build Team “pimped their ride” with the most advanced sound system they could get, and placed several of the appropriate rifles in different areas in the car before subjecting them to several decibel and tone levels worth of sound. However, none of the guns went off. Even taking the guns for testing at a sound studio and getting a custom car specifically designed for sound system contests couldn’t produce a result.
The Build Team tested another, similar myth from the same source, involving an exploded bomb setting off guns placed around the blast zone. This time, one of the guns did fire from the shockwave of the explosion.
This myth came to the MythBusters in the form of a picture that was too graphic to show on air. After testing the handgun and noting the power of the gun’s recoil and the gasses that emitted from between the barrel and the chamber, Adam and Jamie built a pair of chicken hands to test the damage these gasses can cause to an unprotected hand. While Jamie’s less anatomically-correct hand only suffered some minor flesh damage from the gasses, Adam’s hand – specifically created to mimic the bone and joint structure of a human hand – had one finger blown almost completely off, confirming the myth.