Hydrostatic shock

Not to be confused with Water hammer.
Average time until incapacitation decreases rapidly with pressure wave magnitude as magnitudes approach 500 psi (3,400 kPa). See: Links between traumatic brain injury and ballistic pressure waves originating in the thoracic cavity and extremities. Brain Injury 21(7): 657–662, 2007.[1]

Hydrostatic shock, also known as Hydro-shock, is the controversial concept that a penetrating projectile (such as a bullet) can produce a pressure wave that causes "remote neural damage", "subtle damage in neural tissues" and "rapid effects" in living targets.[2][3][4] It has also been suggested that pressure wave effects can cause indirect bone fractures at a distance from the projectile path, although it was later demonstrated that indirect bone fractures are caused by temporary cavity effects (strain placed on the bone by the radial tissue displacement produced by the temporary cavity formation).[5]

Proponents of the concept argue that hydrostatic shock can produce remote neural damage and produce incapacitation more quickly than blood loss effects.[2] In arguments about the differences in stopping power between calibers and between cartridge models, proponents of cartridges that are "light and fast" (such as the 9×19mm Parabellum) versus cartridges that are "slow and heavy" (such as the .45 ACP) often refer to this phenomenon.

Martin Fackler has argued that sonic pressure waves do not cause tissue disruption and that temporary cavity formation is the actual cause of tissue disruption mistakenly ascribed to sonic pressure waves.[6] One review noted that strong opinion divided papers on whether the pressure wave contributes to wound injury.[5] It ultimately concluded that no "conclusive evidence could be found for permanent pathological effects produced by the pressure wave".

  1. ^ Cite error: The named reference fn_(110) was invoked but never defined (see the help page).
  2. ^ a b Michael Courtney; Amy Courtney (2008). "Scientific Evidence for Hydrostatic Shock". arXiv:0803.3051 [physics.med-ph].
  3. ^ Deadly fighting skills of the world, Steve Crawford (1999) pp. 68–69
  4. ^ AK-47: the weapon that changed the face of the war, Larry Kahaner, John Wiley and Sons (2007) p. 32
  5. ^ a b John Breeze, A J Sedman, G R James, T W Newbery, A E Hepper (December 23, 2014). "Determining the wounding effects of ballistic projectiles to inform future injury models: a systematic review".{{cite web}}: CS1 maint: multiple names: authors list (link)
  6. ^ "The Shockwave Myth" (PDF). Fackler ML: Literature Review and Comment. Wound Ballistics Review Winter 1991: pp38–40. Archived from the original (PDF) on May 28, 2008. Retrieved April 11, 2007.