Originally Posted by
QED
Outside of significant experimental error, there really should not be significant deviation of penetration from the mean -- since bare standard gel is homogeneous and the 147 grain HST velocity, mass, and recovered diameter are essentially fixed. Penetration, then, is subject to the well-known laws of physics as was thoroughly discussed in D. MacPherson's excellent book on the subject, for example. Robustly expanding JHP terminal tests in bare gel should generally be quite repeatable, unlike similar tests in tissue.