Which bullet does the 9mm use that .40 S&W and .45 acp can't?

[Trey Veston]

I keep reading in threads all over the internet that 9mm is now just as good as .40 S&W and .45 acp due to "modern bullet design".

Just wondering why that same "modern bullet design" isn't being used by the other calibers to increase their effectiveness by the same margin.

I'm not disputing that 9mm isn't effective for self-defense.

(Though the average American black bear weighs about the same as the average adult American male yet nobody advocates 9mm for bear defense... Hmm...)

So what are these bullets that only increase the effectiveness of the 9mm and no other calibers?

 

[JohnKSa]

...nobody advocates 9mm for bear defense...

Seems to work ok...
https://www.ammoland.com/2018/02/de...s-rate-37-incidents-by-caliber/#axzz5TEHIRlF6

This Alaskan indicates that lately he has been carrying a 9mm himself when in bear country. I'm not sure that's exactly the same thing as advocating it--but it's pretty close if it's not.
https://www.outdoorlife.com/blogs/game-changers/how-pick-right-sidearm-backup-bear-protection

Anyway, that's just a couple of cites from the first page of search results.

I keep reading in threads all over the internet that 9mm is now just as good as .40 S&W and .45 acp due to "modern bullet design".

Ah... Caliber Wars.

Here is my personal, tongue-in-cheek definition for Caliber War.

Caliber War: Any discussion: 1. Containing the words: "I don’t want this to turn into a caliber war." in the original post. 2. Filled with people using personal opinion and preference thinly disguised as evidence and logic to support their caliber choices. 3. In which people who can’t balance their checkbooks pretend to have a firm grasp of physics. 4. In which people who really know the truth about what wins gunfights pretend instead that you can buy it in boxes of 50 from the gun store--and argue about what markings should be on the box.

It's interesting to note that even before "modern bullet design" supposedly leveled the field, no one had been able to categorically prove that any one of the mainstream service pistol calibers was better or worse than any other caliber in the group when it came to actually stopping attackers. Lots of discussion about this parameter vs. that parameter, or statistics vs. gelatin, but when it came to reproducible results demonstrating that one really performed better or worse on the street there wasn't any solid data that the experts could agree on--it still came down to opinion and personal preference. In fact, the FBI's expert, back in 1989 repeatedly hinted in his "famous" treatise that it might take data from a thousand shootings just to find 10 shootings where terminal effect differences due to caliber selection made a difference in the outcome. Hardly a ringing endorsement for putting caliber terminal effect at or near the top of the list of selection criteria when choosing amongst the service pistol calibers.

Strange for a situation where so many people believe there must be an obvious difference. Well, maybe there is an obvious difference--just not an obvious difference that has a practically significant effect on real world shootings. At least not one that anyone has been able to prove. We know that's true because if there was proof, the debate would be over--and it's clearly not over.

Here's an article that contains the text of the FBI's most recent statement. It's worth reading.
https://loadoutroom.com/thearmsguide/fbi-picks-9mm/

Here are some excerpts I like--my added snark is in blue italics:

"Most of what is “common knowledge” with ammunition and its effects on the human target are rooted in myth and folklore" <What sort of blasphemy is this? If my favorite gun-riter rites it it must be rite.>

"The majority of FBI shooters are both FASTER in shot strings fired and more ACCURATE with shooting a 9mm Luger vs shooting a .40 S&W (similar sized weapons) <Crazy talk. Pretending that something other than bullet size could possibly matter.>

"There is little to no noticeable difference in the wound tracks between premium line law Auto enforcement projectiles from 9mm Luger through the .45 Auto." <Obviously false. It must be--it contradicts personal opinion!>​

It sounds to me like your questions and comments should be directed to the folks at the FBI.

 

[Trey Veston]

Entertaining and well written reply, but you didn't answer the question.

What are these magic bullets that only increase the effectiveness of the 9mm and not other calibers.

 

[AZAndy]

I've read lots of hoopla about super-expando 9mm or .38 Special or whatever that says "It's as good as a .45!". What they mean is non-expanding .45 ball. Those same bullets are indeed available for .45, and there are some that expand (in gel) to an inch. Is there a 9mm that expands to an inch? Of course not. It's a faulty comparison in the first place, because two very different things are being compared. It's like saying a butternut squash is faster than a Harley if dropped off a tall building. It's true, but is it useful if you're shopping for a motorcycle-- or for that matter, a squash?

 

[ATLDave]

The reasoning works like this:

• Handgun bullets only incapacitate by their "crush path."
• It is very unlikely that you will cause enough bleeding with crush paths to end a gunfight in a few seconds.
• Therefore, the most important goal is to try to cause a crush path to intersect with some immediately vital structure, such as the brain, spine, aorta, or load-bearing joint.
• The primary obstacles to getting this crush path/vital structure intersection are marksmanship and adequate penetration/weight retention.
• Modern 9mm ammo is sufficiently good at penetration to have about the same chances of creating this intersection as the other service-caliber rounds.
• None of the other service caliber rounds are sufficiently powerful to introduce additional incapacitation mechanisms.

Now, I am personally a little skeptical of a couple of these points, but that's the reasoning.

 

[Kendal Black]

What are these magic bullets that only increase the effectiveness of the 9mm and not other calibers.

I think the best case to be made is that the 9mm is now sufficient, given modern bullets. That does not preclude heavier calibers being "more sufficient" with bullets of similar design. But at that, "more sufficient" is not really a sensible phrase; a thing is sufficient or it is not.

I think what happened is that law enforcement brass needed something to tell the troops, after telling them before that they needed the .40 instead of the 9mm or, in some departments, instead of the .38 Special. Cops old enough to remember the change to .40 were bound to wonder why they were now being handed 9mm pistols.

Something got lost in translation. What they meant to say was that current bullet design and manufacturing technology makes the nine good enough. Whether that's true or not is a separate question and not a question I get involved with. But that's the story as I see it.

 

[Drail]

There are no "magic bullets" - only marketing. Shot placement is far more important than "magic bullets".

 

[walnut1704]

That's because the writers of these "threads all over the internet" have totally misinterpreted the data. Modern bullet design, as Kendal says a couple of posts up, makes the 9mm now considered sufficient. Not "better" than anything else. Just now sufficient, whereas before the recent developments in bullet design the 9mm was found to be inadequate. In this case ballistics experts are judging cartridge effectiveness against a fixed benchmark, not cartridge to cartridge.

 

[danez71]

I don't want to start a caliber war .... but....

The answer is that there isn't any.

Today's 9mm is equal or better than the 40 when it came out.

Thereby making the 40 an answer to a problem that no longer exists.

 

[CraigC]

Those who choose less are always trying to convince themselves and others that they didn't.

 

[rpenmanparker]

Entertaining and well written reply, but you didn't answer the question.

What are these magic bullets that only increase the effectiveness of the 9mm and not other calibers.

You are missing the obvious. No one said that not all calibers were improved by modern bullet design. Of course they are. But there is an upper limit above which it doesn't make any more difference. Put bluntly, dead is dead. You can't be more dead. So if a modern 9 mm bullet that hits its mark will be nearly always effective in stopping an assailant, what does better mean? Nothing. You can't get any better than that no matter what caliber number is written on the casing.

 

[Dibbs]

IMO, while there have been minor improvements, the incident has blown over. Remember, at first,
10MM was supposed to be the new hallmark of bullet performance, embraced by the FBI. Then they
backed down to the 40S&W. Now the worm has turned, and it's back to the 9MM.

 

[Zaydok Allen]

So what are these bullets that only increase the effectiveness of the 9mm and no other calibers?

You are misinterpreting the notion that better bullet construction has narrowed the gap between 9mm and other semi auto cartridges. It hasn't.

Modern bullets have increased the POTENTIAL effectiveness of the 9mm as Kendal Black points out.

It's just a matter of figuring out what compromise you are willing to tolerate. Good enough to stop the threat with extra ammo, or more likelihood of a one stop shot with less ammo on tap. Pick your poison. Just don't fool yourself into thinking a smaller bullet is anything but a smaller bullet.

As is always the case, hiting the target in a vulnerable spot is more important.

If I was hearing story after story of 9mm handguns failing to stop a threat in civilian self defense incidents, I'd be more concerned.

 

[JohnKSa]

Entertaining and well written reply, but you didn't answer the question.

What are these magic bullets that only increase the effectiveness of the 9mm and not other calibers.

The question is a strawman.

Here's the FBI's statement. http://looserounds.com/2015/11/09/fbi-9mm-justification-foia/

It explains their actual position and the rationale for it. The idea that they're placing their faith in magic bullets is a strawman. In reality, what they are doing is exactly the opposite. After all, which fits the definition of believing in magic better? Believing in something that no one has been able to prove after decades of trying. Or drawing a conclusion based on the available evidence.

 

[Dframe]

As an old friend of mine says. "A 9mm might expand, but a 45 will never shrink"

 

[CDW4ME]

9mm HST on a dime, 45 HST on a quarter:


"Just as good" Right?
When/If the definition of "equivalent" includes factors other than terminal potential....
Such as: recoil, capacity, cost

Including criteria other than terminal potential, 9mm is "just as good" as 10mm too. LOL

 

[Chuck R.]

The reasoning works like this:

• Handgun bullets only incapacitate by their "crush path."
• It is very unlikely that you will cause enough bleeding with crush paths to end a gunfight in a few seconds.
• Therefore, the most important goal is to try to cause a crush path to intersect with some immediately vital structure, such as the brain, spine, aorta, or load-bearing joint.
• The primary obstacles to getting this crush path/vital structure intersection are marksmanship and adequate penetration/weight retention.
• Modern 9mm ammo is sufficiently good at penetration to have about the same chances of creating this intersection as the other service-caliber rounds.
• None of the other service caliber rounds are sufficiently powerful to introduce additional incapacitation mechanisms.

Now, I am personally a little skeptical of a couple of these points, but that's the reasoning.

I believe the above to be pretty much the case. Some ft. pounds and a few .10"s aren't as important as shot placement.

And IF all service rounds achieve about the same effect on a target, then the bolded becomes the discriminator. The majority of shooters I've seen, especially the ones that are marginally effective, (BTW, nobody on any gun forum seems to fall into this category, but I see them an awful lot of them in matches and classes), would be better served with a 9mm.

 

[Telekinesis]

I don't think a lot of people realize that the difference between the 9mm and .45 expanded projectiles (HST for this example given the picture above) is a radius of about 1.5mm. Then add in the fact that 9mm, .40, and .45 bullets have been designed to meet the exact same standards regarding minimum AND MAXIMUM penetration depth in test medium, expansion, barrier penetration, etc and it's no wonder that there's no evidence that one performs better than the others.

Also look at how handgun bullets actually cause incapacitation: they either directly hit something electrical like the brain or spinal column (the size of a playing card or your thumb, respectively), the heart (size of your fist), or they make enough holes that blood pressure drops causing unconsciousness. That's it. There's no shockwave or anything like that.

To wrap it all up, the difference is 1.5mm in radius. If you're gonna hit it with a .45, you're gonna hit it with a 9mm, so you should look at all the other factors that reate to ammo choice. Ammo capacity, speed, ammo cost, and hit probabability for a given amount of training time all point to the 9mm.

 

[rsrocket1]

To wrap it all up, the difference is 1.5mm in radius. If you're gonna hit it with a .45, you're gonna hit it with a 9mm, so you should look at all the other factors that reate to ammo choice. Ammo capacity, speed, ammo cost, and hit probability for a given amount of training time all point to the 9mm.

The first hit may be true, but most people have a better chance of getting a follow up shot on target with a 9 than they do with a 40 or 45. And unless the shot hits the CNS, the more holes the better at stopping the threat.

Of course, it's all about practice and being used to the gun.

 

[MidRoad]

Kendal black answered your question pretty well.

There is no magic bullet the 9mm shoots that the 40 or 45 doesn't. Bullets have been improved across the board. But now the 9mm may be a better choice than it was in the past, because now it performs better making it more viable option.

Could look at it this way, a current 9mm could be considered as effective as .45 ammo of the past. However that 45 has also improved so it is more effective than ever before. CDW4ME's picture illustrates there is still a considerable difference in expansion side when comparing the two modern loadings of 9 and 45.

 

[cougar1717]

IMHO, there are two issues that need to be split when talking about this:

1) The bullet technology that the FBI report references from links above is the same across the board - ie expanding bonded bullets. It has solved the jacket separation issues common in traditional jacketed hollowpoints. Ammo manufacturers create and promote SD ammo to sell to LEO's and governmental organizations that buy ammo by the pallet. These manufacturers are not mainly producing your favorite flavor of bonded ammo just to be bought in a box of 20 at the "big box outdoor store." The plain fact is that there is no special technology being incorporated into .355" that isn't in .400" or .451". We can use these products as examples: Speer Gold Dot, Win Ranger T, Rem Golden Saber bonded, Fed HST bonded, which are manufactured in 9/40/45.

2) Issue #2 is not the "What's available?" but the "Why did the FBI go back to 9mm?" It was not solely due to bullet technology and anyone who makes that argument is misinformed. The answer lies right there in the report. They didn't choose 9mm specifically on bullet technology, but also that "participants shot more quickly and more accurately with 9mm caliber." It was not a "caliber performance" issue, but it was a "participant performance issue." Most people would say that both 40S&W and 45acp are more difficult to demonstrate proficiency in comparison to 9mm.

Additionally, the report cites that, "shot placement is paramount and law enforcement officers on average strike an adversary with only 20 - 30 percent of the shots fired during a shooting incident." This should clue the reader into the direction that the FBI is arguing for in their evaluation.
If the previous quote wasn't enough, then," 9mm Luger offers higher magazine capacities, less recoil, lower cost..."

The report reveals the reasoning. It's NOT at "9mm has special bullet technology" line of reasoning.

They concluded that:

• More participants could shoot 9mm more proficiently
• If only 20-30% of shots fired landed, then a greater magazine capacity was important
• And "shot placement was the most critical component to achieving either method of incapacitation."

It is an understandable line of reasoning, even from the perspective of those who do not agree with it.

 

[JohnBiltz]

I keep reading in threads all over the internet that 9mm is now just as good as .40 S&W and .45 acp due to "modern bullet design".

Just wondering why that same "modern bullet design" isn't being used by the other calibers to increase their effectiveness by the same margin.

I'm not disputing that 9mm isn't effective for self-defense.

(Though the average American black bear weighs about the same as the average adult American male yet nobody advocates 9mm for bear defense... Hmm...)

So what are these bullets that only increase the effectiveness of the 9mm and no other calibers?

I will actually answer your question. The improvement is better penetration. .40 and .45 penetrated fine, 9mm was not penetrating as well, at least in JHP. They were emphasizing expansion and since there is no such thing as a free lunch, that expansion meant that two bullets traveling at the same speed that are the same weight the more expanded, larger bullet will always penetrate less. Once a bullet expands its effectively a parachute in flesh. The miracle you want to know about is they limited expansion enough that the 9mm meets FBI standards for penetration.

 

[Walkalong]

There are no "magic bullets" - only marketing. Shot placement is far more important than "magic bullets".

This, it isn't whether the .40 and .45 expand larger with the same quality bullets, it's do they actually stop more bad guys with the same hits or not. I don't know the answer, all I know is there are so many more important factors that have to happen before caliber comes into play it gets lost in the noise IMHO.

Handgun caliber wars are dumber now than they were before all the advances in bullet design, and they weren't all that compelling back then either. I was a staunch .45 ACP fan for a very long time, but things have changed, the 9MM is a better weapon now than it was 30 years ago. I am OK with 9MM, .40, or .45 as a defensive caliber.

YMMV of course.

 

[1911 guy]

From my limited understanding of the subject:
9mm suffered from a bad combination of velocity and bullet jacket design. FMJ in any caliber doesn't expand and 9mm tends to penetrate more than other rounds. JHP bullets didn't stay together at 9mm velocities so you lost both penetration and reliable expansion.
Then bullet and jacket designs improved for the 9mm. They allowed the 9mm to perform as well as the other rounds.
Simplistic and likely flawed in detail, but this has been my understanding of the general idea.
I've seen enough data in the last decade to convince me that both my wife and I own 9mm pistols, although I still carry a .45 due to familiarity.

 

[Random 8]

I've always thought that comparing the "man stopping" capabilities of common defensive handgun rounds is like comparing the off road capabilities of 2wd pickups. I'll take the one with the best tires. All common calibers have benefitted from "better tires." What this has done for 9mm is bring it from the realm of marginal into the realm of solid IMHO. Add in less recoil/better recovery and a higher round count in the same magazines, I'll take the 9mm over the other 2 if I can't use a shotgun or rifle caliber carbine.