Last week we looked at the question of dropping a bullet and firing one horizontally from the same height, and while we conceded that there would be a slight difference in the time they come to earth, we believe that the difference would be undetectable. A second quibble on the subject of shooting bullets came from the same episode, and is also related to guns...
number of quibbles that the elves receive increases greatly when we
contradict a popular source of information. It goes without saying
that wikipedia is one, but another is the excellent popular-science
program "Mythbusters." Mythbusters has shown in one of its
episodes that bullets shot into the air would not endanger those who
fired them, but we think otherwise: while
Mythbusters is a great show for getting people interested in science;
its experiments are not scientifically rigorous.
The elves' figures come from the work of Julian Hatcher, noted firearms expert and pioneer in the forensic identification of firearms and their ammunition. Not being able to easily do practical experiments with real firearms, it's easier to refer to the work of someone who has and who knows his subject well.
Having read the MythBusters transcript we can see a pretty major flaw in their experiment. Their two main experiments don't actually involve firing bullets into the air at all. Rather the bullets are dropped (either into a wind tunnel or from a platform).
Bullets fired from a gun will be rifled which causes them to spin about their long axis in order to give them stability. A bullet which reaches the top of its trajectory still spinning will remain in the upright position due to angular momentum and, therefore, start to fall back down bottom first (as mentioned in the work carried out by Major Hatcher). A bullet which is simply dropped will not have this kind of stability and so will be much more likely to tumble, thereby reducing its terminal velocity and making it less deadly.
It's also interesting to note that of the two firearms experts giving an opinion in this debate (the aforementioned Julian Hatcher and Dr. David G Mohler who was consulted in the Mythbusters show), both were of the opinion that falling bullets are deadly.
Currently the only people who are saying falling bullets aren't deadly are the Mythbusters presenters and those who have watched the show.