9 mm, vs 40 S&W vs 45 acp

For years the debate over what is the best handgun caliber has raged. Some people swear 9 mm with a small hollow point bullet travelling very fast (1200 fps) is the best. Some feel that the large 45 caliber HP bullet travelling at a more sedate 800 fps is better, providing they both expand upon impact. The much newer 40 S&W has following too, stating that a moderate weight HP bullet travelling at a moderate speed is the best as it takes almost the speed of a 9 mm and places it almost the the same mass as a 45 ACP.

Well, here's my researched input...

--A 9 mm bullet (0.355 caliber) has an impact area of 0.098 inches squared.

--A 40 S&W bullet (0.40 caliber), which is 10 mm in size, has an impact area of 0.126 inches squared, which is about 27% larger then a 9 mm.

--A 45 ACP bullet (0.452 caliber), which is over 11 mm in diameter, has an impact are of 0.160 inches squared, about 63% larger then a 9 mm.

Assuming the bullets are FMJ and or HP bullets that do not expand upon contact, a 45 ACP will cause significantly more damage then a 9 mm or 40 S&W simply due to its initial contact area being much larger.

But, alas, life is not that simply. There are 9 mm HP bullets that have been FBI tested to constantly expand to 0.60 inches in diameter, or slightly larger. Well, this is a lot bigger then a 45. Some, 40 S&W bullets can constantly expand to 0.70 inches in diameter. And then there are 45 ACP bullets that were tested to constantly expand to 0.78 inches in diameter. So, a 9 mm that does expand fully is better then a 45 acp which does not. Ok, you are asking, what about the extra speed of the 9 mm vs a 45 ACP? Most 9 mm bullets, even with their extra speed still have less energy then a 45 ACP bullet at a slower speed simply due to the much greater mass of the 45 acps bullet.

But, not all bullets expand. There are report after report, after report of HP bullets of all calibers and weights not expanding due to the HP being filled in with denim, cotton, flesh, etc which essentially causes a HP bullet to become FMJ. All tests of handguns bullets show penetration of 8 to 16 inches of ballistic gelatin, with most being 8 to 13 inches. You want a bullet that will not go too far, as you want it to expend all its energy into the target and not exit the target, but penetrate deeply enough to hit vital organs.

So, which is better? The biggest HP/SP bullet with the most energy that properly expands.

http://www.hipowersandhandguns.com/38%20Special%20Expansion%20Tests.htm
http://www.firearmstactical.com/tactical.htm
http://www.handgunsmag.com/ammunition/bullett_071207/index.html
http://user.tninet.se/~scj351g/handloading/expansion.html
http://www.frfrogspad.com/terminal.htm