A
writer friend and I were talking a while back. He mentioned a book he had read
in which a character under fire heard a bullet strike a tree, then heard the
report of the rifle. My friend suggested this was unlikely, as the speed of sound
is much greater than that of the bullets of the era—the Old West.
I
disagreed, and we left it at that.
However,
curiosity got the best of me, so I thought I’d do what they tell you to do on
Sesame Street: “Look it up.” It took a few hours and lots of mouse clicks to
reach a number of relevant web sites. Here’s what I learned about the speed of
sound and the velocity of bullets fired from a few rifles in common use at the
time in question.
Sound
travels through the air at 1,125 feet per second. That varies somewhat,
affected by temperature, humidity, and wind. And, of course, sound waves
dissipate and the noise fades with distance. The velocity of bullets varies as
well, depending on wind and distance, and the bullet loses speed the farther it
travels.
But,
all things being equal, a bullet fired from a .52 caliber Spencer repeating
rifle would lose the race, lumbering along at a paltry 931 to 1,033 feet per
second.
The
race with a .44 caliber round from a Henry rifle would be a dead heat, the
bullet leaving the barrel at 1,125 feet per second.
A
bullet from a Winchester .44-40 Golden Boy outruns sound at 1,433 feet per
second.
The
old-time Hawken rifle, .50 caliber model, spit out lead at 1,600 feet per
second.
Winning
it all is the Sharps .50 caliber, which, depending on grains of powder in the
cartridge, fires bullets that fly 1,448 to 1,814 feet per second.
None
of which matters. But how else is an old man with no gainful employment
supposed to spend his time?