[Frank Ettin]

Originally Posted by SRH78

...I can tell you this, a 45 Colt and 454 Casull shoot the same diameter bullet and neither shoots 2500 fps but the difference on game is like night and day. With the Colt, I can shoot cottontails and eat right up to the bullet hole. With the Casull, there isn't much left of a jackrabbit...

Again, your comparisons aren't useful. There's a big difference in body mass between a rabbit (cottontail or jack) and a human.

Originally Posted by SRH78

...A 45-70 at 1700-1800 fps with a soft nosed bullet will leave a huge exit wound on a hog...

And that's a matter of the combination of high sectional density of the bullet, a heavy bullet and good bullet construction producing meaningful expansion at the relevant velocities.

But let's see what some people with professional credentials who have scientifically studied the subject say:

• For example Dr. V. J. M. DiMaio (DiMaio, V. J. M., M. D., Gunshot Wounds, Elsevier Science Publishing Company, 1987, pg. 42, as quoted in In Defense of Self and Others..., Patrick, Urey W. and Hall, John C., Carolina Academic Press, 2010, pg. 83):

  In the case of low velocity missles, e. g., pistol bullets, the bullet produces a direct path of destruction with very little lateral extension within the surrounding tissue. Only a small temporary cavity is produced. To cause significant injuries to a structure, a pistol bullet must strike that structure directly. The amount of kinetic energy lost in the tissue by a pistol bullet is insufficient to cause the remote injuries produced by a high-velocity rifle bullet.

• And further in In Defense of Self and Others... (pp. 83-84, emphasis in original):

  The tissue disruption caused by a handgun bullet is limited to two mechanisms. The first or crush mechanism is the hole that the bullet makes passing through the tissue. The second or stretch mechanism is the temporary wound cavity formed by the tissue being driven outward in a radial direction away from the path of the bullet. Of the two, the crush mechanism is the only handgun wounding mechanism that damages tissue. To cause significant injuries to a structure within the body using a handgun, the bullet must penetrate the structure.

• And further in In Defense of Self and Others... (pp. 95-96, emphasis in original):

  Kinetic energy does not wound. Temporary cavity does not wound. The much-discussed "shock" of bullet impact is a fable....The critical element in wounding effectiveness is penetration. The bullet must pass through the large blood-bearing organs and be of sufficient diameter to promote rapid bleeding....Given durable and reliable penetration, the only way to increase bullet effectiveness is to increase the severity of the wound by increasing the size of the hole made by the bullet....

• Urey Patrick was in the FBI for some 24 years, 12 of which were in the firearms training unit where he rose to the position of Assistant Unit Chief. John Hall is an attorney who spent 32 years in the FBI, including serving as a firearms instructor and a SWAT team member.

And in case you or anyone else is interested, I've attached a copy of an FBI paper entitled "Handgun Wounding Factors and Effectiveness."