I had seen that. That's another site with the same name but wasn't associated in any of my search tools.
This piece is a little out of date. I know some guys on here getting this kind of velocity. If they can hit something point blank maybe we can see some real shock wave results.
@Zen Archery are you listening?
The notion of "hydrostatic shock" is a silly one. The sound speed of muscle tissue has been measured to be about 5150 fps, and that of fatty tissue around 4920 fps (A Cavitation Model for Kinetic Energy Projectiles Penetrating Gelatin, Henry C. Dubin, BRL Memorandum Report No. 2423, US Army Ballistic Research Laboratories, December 1974
). Even varmint bullets do not have an impact velocity this high, let alone an actual penetration velocity exceeding 4900 fps. Unless the bullet can penetrate faster than the inherent sound speed of the medium through which it is passing, you will not observe a shock wave.