9mm or .40?

[76shuvlinoff]

I have an XD40sc for carry with a drop in 9mm conversion barrel for plinking.

Issue resolved for me.

 

[Gungnir]

This makes no sense. Why did you choose to compare a Double Tap .40 with a Federal Hyrda-Shok 9mm? Not only does DT make the same JHP round in 9mm with significantly more energy behind it than the Hyrda-Shok, but Hyrda-Shoks are an out-dated design and quite frankly a sucky performer when compared to newer bullet designs. Besides, the +P designation simply means it's loaded to the upper end of the load's allowable pressure range . The .40s&w doesn't have a +P designation because it's usually already loaded to very high pressures.

I used Hydra-Shok in 9mm because I had the data, same as the Double Tap in 40, saved me digging around the internet, and I did explain I did not include +P or +P+ for 9mm. Obviously this did not apply for the 40, since it's a newer cartridge. Now, +P only means up to 10% higher pressure above SAAMI standard, and +P+ means above 10% up to test pressure, which actually doesn't turn out to be a lot of increase in muzzle velocity.

Here's some readings I dug out averaged across 5 rounds Millennium 2 Chronograph I've taken from my Wife's HK P30 3.86" barrel I didn't try the DoubleTap

9mm NATO 124g FMJ 1200fps
Cor Bon 115gr +P+ JHP 1310fps
Remington 115gr +P JHP 1280fps
Federal 124g Hydra-Shok 1160fps

So while the Cor Bon is 150 fps faster than the Hydra-Shok, it's also 9 grains lighter, and it's only gained gained 9% more energy (92% of the weight * (113% velocity increase)^2)/2

Penetration is the most important part of "stopping power" next to good shot placement

Not precisely true, according to the FBI, who discounted hydrostatic shock, penetration and CALIBER are the most important for "stopping power", the permanent wound channel is the combination of the penetration, and the caliber, if the round is expanding (hollow point) then the wound channel will expand with that expansion, a .40 S&W 180gr JHP can expand to a maximum of 0.68 inches and penetration of 13 inches, a 9mm 147gr can expand to 0.62 inches and a penetration of 13.25. Doing a quick volume calc for the expanded caliber (assuming instant expansion) shows a wound cavity for the .40 as 4.7 cu in but 9mm is 4.00 cu in (or an 18% increase in wound volume for the 40 over the 9). Those expanded sizes come from the rounds used in Doug Carrs testing that was the basis for the 10mm joke above.

Ultimately they're both good rounds, my wife uses the 9mm, I personally prefer 40 S&W and 10mm.

YMMV

 

[easyg]

I respect the 9mm caliber, and it is certainly capable of stopping a human attacker (with careful ammo selection), but I'll take a .40S&W or .357Sig over the 9mm every time.

During the "wonder-nine" years (the 80's), the 9mm developed its reputation as a rather poor man-stopper.
And despite improvements in ammo that reputation continues to haunt the 9mm.

 

[NinjaFeint]

I never said they were, I said that the FBI switched because they found that during the 1986 Miami Shootout they underperformed to what was expected (which is anemic). Whether that was political "blame the cartridge" or not, isn't relevant. Here's the facts

William Matix: Killed after being shot 6 times.
Michael Platt: Killed after being shot 12 times.

Of the 54 metallic rounds fired by the FBI (there were also 5 shotgun shells fired) 42 were 9mm, the rest were either 357 Magnum or 38 Special +P. So statistically we can expect 14 of the rounds in the two suspects to be 9mm (assuming that all the agents were equally bad shots) and we also know that they were killed outright or incapacitated by a 357 Magnum so would you argue with that data that in 1986 the 9mm was anemic, or under-performed in that situation? As an aside both these suspects toxicology reports came back clean.

I am pretty sure there are better rounds produced since 1986. The CorBon DPX is one of them. Again, the .40 has more power but the 9mm will do fine if that is what you can shoot the best.

 

[bestseller92]

I think that if one researched it enough, one could find anecdotal evidence of "stopping failures" with any handgun round.

That having been said, I am quite happy with my G22 loaded with Winchester Ranger 155 grain JHP and my G26 stoked with Federal 115 gr. +P+ JHP.

Either is better than fingernails.

 

[m2steven]

If you check the ballistics charts for +p or +p+ 9mm ammo, you'll see that there is plenty of energy in those rounds. Bigger is always better if you shoot it well, but you should not feel undergunned in the least with a 9mm pistol pointed in the correct direction. I love my 40 and 45's, but i always carry a 9mm. I shoot followup shots better with most of the 9's.

 

[Philo_Beddoe]

40 or 9 are both good with very little difference in the jello tests

I went with 9 because the ammo is cheaper, if you are issue 40 that is what i would shoot

 

[makarovnik]

"Can't" Search?

Go with the .40