What exactly is hydrostatic shock and what fps is the minimum to cause it?
I think it's more of an energy thing than a fps thing... so mass (bullet weight) AND speed (fps) both factor. The energy transfer causes damage to surrounding areas outside the exact path of the bullet (which obviously causes disruption). You can see this when you butcher something, or when you open up a chest cavity. Larger areas surrounding the bullet path are jellified or otherwise disrupted. I've seen it with the 243 many times on deer.
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