Supersonic Crack

[86alaskan]

So, does anyone know if the super sonic crack we hear increases in volume as speed increases? I was shooting my 300WM suppressed this weekend and noticed a distinctly louder crack from a 110gr RN bullet going ~3500fps vs a 185gr vld doing 2900fps. It seems to me like it would, but all I had to measure it was my ears. The 185 was hearing safe but the 110 produced a clear ringing.

 

[FearNoWind]

If there is any increase in the audibility of the sonic "crack" between those two bullets it is more likely due to the geometry of the bullet combined with the speed than the speed alone.

http://www.nasa.gov/centers/dryden/pdf/88387main_H-2068.pdf

 

[4xforfun]

Sometimes when I am in the 1000 yard pits I notice that the bigger 30 cal and .338 cal bullets seem to be louder. Now, is that due to the size or maybe the fact that they may be going faster. I don't know. just my .02, and I can't prove it. lightbulb

Tod

 

[FearNoWind]

from http://forum.accurateshooter.com/threads/supersonic-cracks.3904504/
"NASA did some testing circa 2013 "NASA's Shaped Sonic Boom Demonstration" which revealed that an aircraft's shape affects the intensity of the sonic boom it creates at supersonic speeds. ... it's the shape of the mass not the mass."

Pretty much answers the question I think.