9mm/40SW/10mm/.357 Sig/.45 Comparo


August 7, 2007, 05:51 PM
No one, including me, ever gets tired of comparing ballistics and stopping power for the semi-auto cartridges we love best: 9mm, 40SW, 10mm, .357 Sig, .45 ACP.

I included, where possible, a sampling of different manufactures (ex: HP and FMJ) for each one, including +P where I had the data.

Sure, there are others, but these are the preemo, and most commonly-discussed, semi-auto calibers for SD. I've attached a little chart in Excel that compares ballistics for these cartridges, including both momentum and TKO. Momentum is knockdown power in foot pounds, and TKO (Taylor Knockdown formula) is momentum multiplied by the caliber in inches. I added these calculations because momentum and TKO come about as close as any single number can to expressing a cartridge's knockdown, or stopping, power. No single number, and maybe no combination of numbers, can actually capture stopping power, and obviously shot placement and other factors matter greatly, but these make a good starting point. [The highest TKO number on my chart is 13.40 (.45 ACP, 230-gr. +P load) - by comparison, a 30-06 in 180-grain at 2,700 fps yields a TKO of 19.7.]

The 2nd worksheet is a condensation of the first, with just the highest momentum numbers displayed.

It is not always possible to directly compare the same bullet weight. The heaviest 9mm slug for which I could find tables was 124-grain, but the smallest .40SW and 10mm was 135-gr. Anyway, they're close enough.

I thought the .40 SW would exhibit far more power over the 9mm than actually seems to be the case. Use bigger bullets in the .40, though, and it starts to really pull away from the 9mm. On the other hand, in the same bullet weight, the 40SW compares rather well to the .45. Since I have 9s and .45s, and love them, nothing in the tables is telling me to buy the .40; but that's just my preference and it could just as easily be argued that the .40 does a good job of replacing both. Other factors like single vs. double stack must be considered, but ballistics plays a definite role in handgun selection.

I think the tables make it clear that (excepting the 9mm on the low end and 230-gr. .45 on the high end) none of these cartridges is compellingly more "powerful" or possesses significantly more "stopping power" than others when comparing the same bullet weight. We all knew this, I realize, but the numbers are fun, and the momentum and TKO add a twist.

If you enjoyed reading about "9mm/40SW/10mm/.357 Sig/.45 Comparo" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
August 7, 2007, 06:43 PM
In my opinion, I think .357SIG is a bit better than .40S&W.

.40S&W only gives maybe 100lbs knockdown power than .357SIG and a .357SIG round can travel at 1600 fps - whereas the .40 maxes out at 1250 fps. Wouldn't this give a .357 round a high chance of defeating light armor?

August 7, 2007, 06:50 PM
My answer to the debate....

Pick the one with which you want to get shot.

None of them?


I own a pistol in all of those calibers...and 99% of the time carry a 9mm or a .45GAP. Y'all can bet your mortgage payment I'd politely decline being holed by any of them. They can, in my opinion, all be relied upon for journeyman service in self defense.

August 7, 2007, 08:27 PM
1. 10MM
2. .45ACP
3. .357 sig
4. .40 S&W
5. 9MM

August 7, 2007, 09:14 PM
For sheer knockdown, the .45 in 230-gr. is the one. For penetration, the .357 Sig. But any one is adequate for SD.

August 7, 2007, 10:27 PM
Massad Ayoob writes in AH article, after attending a Winchester LE seminar, that the 40SW is the clear-cut best seller in the police sector, followed by the 9mm and .45 ACP. The best selling cartridges to LE are:

.40 SW
.45 ACP
.357 Sig

This is Winchester data. They also have a 9mm 147-gr. load, for which I do not yet have data.

If you enjoyed reading about "9mm/40SW/10mm/.357 Sig/.45 Comparo" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!