9mm vs. .40S&W (a different aspect to the question)

[Bryansix]

Speed and Accuracy... I like it.

[jlbflyboy172]

My range experience is that I see way more people shooting .45 ACP than .40 S&W by a factor of about 3-1. My particular range of choice though may have a particular demographic that may lend itself to a greater popularity of .45. Many LEOs shoot there and guys from various agencies.

[ap3572001]

9mm vs .40.....

I have both. Carry and carried both on and off duty.

To me its a Glock 17 with 17/33 rd magazines VS. Glock 22 with 15/22 rd magazines . Both loaded with Winchester Rangers 180 or with Federal HST 180 ( THE ONLY AMMO I CAN USE).

Which one I like better ? G22 GEN4 . But would be very happy with either one.

[hermosabeach]

You might want to take a look at the "Hatcher Formula" for stopping power

http://www.abaris.net/info/ballistics/hatcher-table.htm

KE= 1/2 mass * velocity squared
So the 9mm in general will have more kinetic energy as 1/2 of 115 grains or 1/2 of 180 grains is small versus the square of the velocity

Momentum is mass * velocity

Hatcher Formula favors a flat tipped round

9mm are rounded FMJ
While many .40 are a truncated cone with a flat tip

For heavy critters, momentum wins. Slow heavy bullets- think of a buffalo round - 405 grain lead bullet

I think that the heavier bullet would do better on baracades.

Either way- pistols suck- they are just easy to have with you

[RobertSmith]

I would say comfort dictates what you should carry. I'm sure that a 9 would be just as effective as a 40.

Given that if you feared for your life and fired a shot, you would probably give 'em 10 or more rounds. Enough to do the job, in my opinion.

I am a 40 cal person myself.

[hermosabeach]

I also found a test of ballistic tests

http://www.americanrifleman.org/m-articlepage.aspx?id=4547&cid=19