To capture the "real" sound of such a big gun is technically rather difficult.
That "Challenger Sound" is most likely the (poor) result of capturing with a microphone specially tailored for speech, which filters out low sounds (rumbling from wind etc). Most likely there's high-pass filtering at work as well (to get rid of feedbacks, hissing etc.)
And the inevitable limiter (preventing overmodulation) will have low-pass filter effect,too.
Therefore we hear the gun like we would through a telephone ...
Good sounds should be recorded from 50..100m away (you are not (virtually) standing right next to your units in SP), using full-range (recording studio quality) condser micros and DAT equipment.
Any volunteers, to get that together and make some recording sessions at shooting ranges?
Stefan