[Vigilantcitizen]

The problem with stopping power in military ammo is the restriction to use of fmj bullets. 9mm has plenty more stopping power than a 45 if the 9 is a heavy HP and the 45 is a ball round. Without high performance bullets the bigger the hole the more stopping power and a 45 makes a larger hole than a 9 by far.

During the small arms portion of USN gunnery school, this redneck, know-it-all, Georgia boy laughed aloud at the instructors claim that a .45 has more stopping power than a .44 magnum.

Here's how he explained it...

The .45 round has a lower muzzle velocity than the .44 and other magnum rounds. This enhances the maximum expansion characteritics of the projectile in human flesh, making a large exit wound more of a reality at close range.

There is a point of dimished returns. Too much muzzle velocity, and the projectile can easily pass through the human body without expanding.

[templar]

Too much muzzle velocity, and the projectile can easily pass through the human body without expanding.

Depends on the bullet design and construction. I.e., in rifle bullets varmint style bullets are nearly useless on large game since they (basically) explode on impact and don't have any penetration in spite of velocities in the mid to high 3000's. Likewise, the good old 45/70 with a decent soft or hollow point can give both extreme penetration in large animals with terrific expansion in even shallow depths with less than 2000 fps velocity. Bullets need to be designed for the velocities they will be used at to give maximum energy transfer to the target, and an inappropriate bullet for the velocity will probably give poor performance regardless of caliber. High velocity projectiles have a quality all of their own regardless of style that low velocity projectiles do not have.