I've been looking for a good hollow point .40 personal defense round to use in my M&P and during my google search most come up with 180 gr rounds.
Whats your opinion? Lighter faster bullet or the slower heavier bullets?

I remember reading some data on some lighter .40 S&W loads that were right up there with the warmer .357 mag's, but I'm pretty sure they were hand loads. Check with the guys over there.

Faster isn't always better. Sometimes heavier bullets will penetrate deeper because of the energy it carries.

I'm a big fan of shooting the bullet weight for a caliber it was developed with. I like the 158gr bullet in the .38 Special, the 230gr bullet in the .45 Auto, the 124gr bullet in the 9mm and I Think the 40 S&W was developed using a 180gr bullet but I'm not completely sure about that.

I'm not telling anyone this is the only way to choose a bullet weight, it's just my way...

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SWCA #3437

I don't know how valid my reasoning is but I carry a 165 gn. Speer Gold Dot in my Sig P239 because the barrel length is only 3.6 inch. In my 4.5 inch XDm or 6.5 inch 610, which alternated as house guns my choice is a 180 gn Winchester Ranger-T. My thinking is that lighter bullet will get closer to optimum velocity in my Sig than a heavier bullet.

To be honest I suspect that my reasoning is good theory but in actual practice it probably doesn't mean diddly. However, that 165 gn God Dot does have a distinct bark to it at the range and there are times when that can be a bit fun.

One benefit of the 40 S&W is that there is a rather large variety of loads available for it. Typically 165 and 180 gn loads are common in both range or SD offerings. However, you can get loads with bullets as light as 135 gn. if you shop on the net. Cor-Bon offers a 135 gn. JHP screamer at 1325 fps and 525 ft.lbs. that barks a bit like a 357 Magnum if that floats your boat.

Personally, I'm a grumpy old man so I like heavier bullets. Partly because I'm old fashioned enough to prefer a heavier rock to some light weight pebble for defense even when the math says lighter can be more powerful. The other reason is that I find heavier loads seem to have a recoil impulse that is a bit easier on my wrist, unlike the harsh whip crack of that light Cor-Bon screamer.

Any modern, expanding .40 S & W round will perform fine. It was first available in the 180 gr weight but statistics show good results from 135 and 155 gr ammo also. The factories are pretty good at tailoring bullet construction to the caliber and velocity for the necessary balance of penetration and expansion.

I suggest trying several different brands and weights of quality JHP ammo and see which gets along best with you and the gun. Hope this is helpful.

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Alan
SWCA LM 2023, SWHF 220

For a long time I believed in lighter and really pushed the light. My 357 Sig load was a 90 grn JHP at around 1700 FPS. After seeing how those light bullets just exploded on the surface of some targets, I have now moved toward the heavy end so my carry load is a 125 grn bullet in 9mm and 357 sig or a 180 in 10mm/40.

While heavys appear to kick more, that gives more recoil impulse to run the slide and action helping reliability.

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SWCA 1646

Around here the Border Patrol carries 155 gr. I have tried 155, 165 & 180 in my XD & M&P's and the 180 seems to be the least accurate of the bunch. I usually carry 165 although I plan on loading some 180 XTP to see if I can improve on the accuracy

You can't go wrong with big lead.

I tend to like mid to heavy for caliber. That said, there is a ton of good information out there. The IWBA is a good source for a lot of test data used by LE and military. Here's a place to start, second post has some ammo recommendations by Dr. Gary Roberts:
Self Defense and Duty Load Information - 1911Forum

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ΜΟΛΩΝ ΛΑΒΕ

He's a dentist for cryin' out loud. People seem to quote him like he's a Dean of manstopping.

If you want to know what works then you have to see what people who actually shoot people are using and having success with and not dentists.

Do you have any idea of what the IWBA does? He may be a dentist, that is not his claim to fame in the field of wound ballistics. Look up Martin Fackler, or the IWBA. They have done consulting and analysis for the FBI, numerous LE agencies, etc.... the people you refer to as " people who actually shoot people."

Take this from a different angle, who do you believe has better credentials? What is wrong with GKR'S recommendations? Do you actually have anything to add to the discussion, or is a criticism that a researcher is "a dentist for cryin' out loud" sufficient in your mind to disqualify his work?

Got something to say that has some solid backing? I'm sure we'd all benefit.

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ΜΟΛΩΝ ΛΑΒΕ

Just a little background on Dr. Roberts:
"Dr. Roberts is currently on staff at Stanford University Medical Center; this is a large teaching hospital and Level I Trauma center were he performs hospital dentistry and surgery. After completing his residency at Navy Hospital Oakland in 1989 while on active military duty, he studied at the Army Wound Ballistic Research Laboratory at the Letterman Army Institute of Research and became one of the first members of the International Wound Ballistic Association. Since then, he has been tasked with performing military, law enforcement, and privately funded independent wound ballistic testing and analysis. He remains a Navy Reserve officer and has recently served on the Joint Service Wound Ballistic IPT, as well as being a consultant to the Joint FBI-USMC munitions testing program and the TSWG MURG program. He is frequently asked to provide wound ballistic technical assistance to numerous U.S. and allied SOF units and organizations. In addition, he is a technical advisor to the Association of Firearms and Toolmark Examiners, as well as to a variety of Federal, State, and municipal law enforcement agencies. He has been a sworn Reserve Police Officer in the San Francisco Bay Area, where he now he serves in an LE training role."

This can be found at: http://www.dtic.mil/ndia/2008Intl/Roberts.pdf

Obviously, I tend to take his recommendations seriously. But, it's a free country, and anyone can follow whichever "Dean of the manstoppers" they want. Read the research and come to your own conclusions, ymmv.

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ΜΟΛΩΝ ΛΑΒΕ

Ive shot several bullet weights in my M&P 40 and I seem to shoot better with the 165 gold dots. But again, your gun might like a different bullet weight.

This is my logic: 180gr ammo uses less powder because the bullet fills more of the case. There is less case volume for the powder to start that rapid expansion of gas that pushes the bullet down the barrel. Less powder means less recoil and flash. The slight increase in bullet mass over the 155 or 165 grain bullets has always seemed minimal in feel while powder increase is exponential in pressure building. Maybe I'm wrong or maybe I'm stretching it, either way I prefer 180gr ammo and I seem to shoot better with it.

I've worked two police shootings with the Winchester 180 grain bonded .40 round. Both involved cars, and in each case the driver was killed and one or more passengers wounded, so they may not correlate well to a typical non-LEO shooting, if there is such a thing.

I can tell you that this round will penetrate a windshield, a head, a head rest and part of a back seat and still weigh about 175 grains. It was truly impressive.

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“What you got, ain’t new.”

As I've said in other threads, the ammo you should use is the ammo with which you are most accurate.

But I look at it like this. If you could get a boxer to punch someone, and needed him to knock out the other guy with one or two punches, would you get the flyweight, the middleweight, or the heavyweight? You'd get George Foreman or Joe Frazier, not the little guy.

Not very scientific I know. Perhaps even overly simplistic. But I know energy equals mass time speed of light squared. But everyone seems to be concentrating on the speed part of the equation, and paying little to no attention to mass. What does more damage? An Escalade hitting you at 50, or an Malibu hitting you at 60?

I like heavier bullets even though they are slower than the lighter ones. The so called heavier ones are usually the ones that the gun was originally designed to shoot (230 grain RNL for the 1911 Pistols and 158 grain for the .38 Specials) and will usually be the most accurate with. I would rather have 100% reliable functioning with a 230 grain ball bullet in a 1911 Pistol than a 185 grain HP that will penetrate less, have greater recoil, will probably shoot low and might have a tendency to jam. But I am just old fashioned........

Chief38

Actually, it is 1/2 (mass) X (velocity) squared. If you have reloading data that get your bullets to the speed of light, that would be an effective SD load! .

If effectiveness of a round was simple kinetic energy, you'd want to go with high velocity, since energy increases as the square of velocity but only proportional to mass. So a 2X heavier bullet gives 2X more energy, but 2X velocity gives 4X more energy. How bullets work on targets is much more complicated, unfortunately.

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Alan
SWCA LM 2023, SWHF 220

I guess I don't remember as much of my high school math as I thought I did. I thank you for the correction.

I think part of my preference for a heavy bullet is felt recoil. Everyone is different, but for me a 147gr 9mm generates less felt recoil than does a 115gr or 125gr. It's more of a push than a snap.

Still, and I know this is really simplistic, but... safeties are faster than linebackers. Linebackers weigh more than safeties. Getting hit by the linebacker hurts more. Trust me.

Still working on getting the bullet to the speed of light thing...

The IWBA is now a long defunct organization. Here's the link that the so called "Firearms Tactical" pages gives. http://www.iwba.com/

I don't listen to those who pontificate the virtues of shooting blobs of jello and then have them tell us which loads are "best" to use to fend off human attackers, who most definately are not made up of blocks of chilled ballistic gel that are callibrated with a .177 steel BB shot from a BB gun before applying some "IWBA Approved" bullets into the tissues of someone who's wanting to maim or kill me!

As stated before, if you have a better source of information, feel free to share. Your post adds nothing to the discussion except your opinion, and even that lacks support.

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ΜΟΛΩΝ ΛΑΒΕ

I would say go with either HST, Ranger T or Gold dot in 165 gr or 180 gr. These rounds have a good street record. The 180 gr HST that I use in my G23 have good street results in Columbus and San Diego. Go to M4Carbine.net and choose from Dr. Robert's list of approved rounds or go to Glocktalk.com and ask Massad Ayoob in the self defense forum. The only exception would be the 165 gr Gold dot round because I have seen gel tests where it failed to expand.

I like the lighter (135gr) bullets in .40sw due to the lighter recoil.

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Centennial Every Day

In the .40 s&W all the bullet weights using JHP are quite effective and the solids are no slouch either but the lighter JHP loads (<180gr) show a slight advantage in the Marshall Sanow continuing study. See the data at 40 S&W Stopping Power

I think the reason this debate goes on forever is because both light and heavy bullets work. These days, I don't think you can make a mistake. Personally, I prefer the heavier bullets because of the superior penetration, and because no matter the velocity it's always a heavy bullet.

I'm an old guy, and grew up reading Elmer Keith and Skeeter Skelton, so that's what formed my opinion.

I generally prefer heavier bullets,but there are some mid weights in .40 that work really well. The 165 gr. Ranger comes to mind.

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