Board Thread:Off Topic/@comment-3965075-20150620202833/@comment-25396609-20150719015539

A .38 special bullet travels at 207 m/s delivering roughly 277J of force.

The reason a bullet pierces is that the force is concentrated into the tip, driving it through rather than distributing the force.

A first carrying the same energy as a .38 special bullet will deliver the force differently, and a good way of examining how it delivers the force is to look at a bullet proof vest, which is thicly woven fiber. the fibers distribute the force over a wider area, causing the person struck to be thrown backwards rather than their flesh pierced.

using a comparison with a specific meaure of force, and changing it to reflect the surface area over which the force is distributed, allows one to more accurately determine the distance a person will be sent backwards when struck.

Bullets can fly quite differently. based on the rifling, shape of the tip, projectile size, grain count, etc. they will drop differently, be affected by wind differently, deliver more or less force over a larger or smaller area, and so on.

Why are OCs different? because due to the inability to accurately SHOW how these things work, we rely on TELLING how they work, which in certain cases requires either a clear example or specific numbers, as with yours. that's why we try to specify caliber on guns, why we put measurements for weapons.