[Yo-Yo]

Goddard amply proves the fallacy of "knock-down power" by calculating the heights (and resultant velocities) from which a one pound weight and a ten pound weight must be dropped to equal the momentum of 9mm and .45ACP projectiles at muzzle velocities, respectively.

Also demonstrated as a fallacy by the Mythbusters in the episode Blown Away.

[marktwain]

Goddard amply proves the fallacy of "knock-down power" by calculating the heights (and resultant velocities) from which a one pound weight and a ten pound weight must be dropped to equal the momentum of 9mm and .45ACP projectiles at muzzle velocities, respectively.

A silly argument. Momentum is equal and opposite, energy is not. So? Defining "knock down" power as equal to momentum makes this a straw man argument, imho.

Much of "stopping power" is psycological.

[FromTheSidelines]

I once worked out the energies of a 45 ACP @ 1000 FPS with a 230 grain bullet, and a typical semi-pro middleweight fighter. Turns out the energy delivered by the boxer's fist was a bit higher than the 45 ACP. And someone like Mike Tyson in his heyday was around 2.5 times as strong as the 45 ACP.

The difference, however, is that the energy from the fist is spread out over 10 square inches and doesn't penetrate.

But the point is: if a punch won't knock you over, a shot from a pistol probably won't either - at least not from the energy transfer.

NOTE: oddball pistols like the 460, S&W500, AE50 and others are excluded as they're more of a hand cannon and really not suitable for concealed carry