I've noticed a trend in recent years since the FBI dropped .40 S&W in favor of 9mm Luger and their subsequent explanation as to why.

According to the FBI, based on extensive testing they had performed, 9mm Luger, .40 S&W, and .45 ACP were all pretty much equal in terms of effectiveness, ergo it was found most efficient to adopt the 9mm Luger due to lighter recoil, faster follow up shots, greater ammo capacity, not to mention the lower cost of ammunition.

Ever since then, pretty much every article published by major magazines/outlets has repeated this statement, and pretty much every article written in regards to .45 ACP for self-defense also covers 9mm Luger and/or .40 S&W, ultimately arriving at the conclusion that 9mm Luger is better because the FBI says so.

Now let's not even get into the fact that the FBI hasn't really revealed the details or methods they used in their testing, nor begin questioning exactly what sort of methods could have possibly been used to arrive at the conclusion that 9mm Luger is equal in effectiveness to bullets of greater mass/energy foot pounds, and let's most certainly avoid making rash assumptions/accusations in regards to the FBI adopting the cheapest cartridge.

What I would really like to see discussed here today is the .45 ACP and nothing more. Not how it compares to other cartridges, just the .45 ACP cartridge on its own, something that nobody can ever seem to do anymore.

In this thread, let's discuss the merits of the .45 ACP cartridge, it's strengths, what it's good for, where it shines, and how it's still relevant today.

This is NOT a 9mm bashing thread, so please refrain from posting inflammatory comments on 9mm Luger, (or any other cartridges for that matter) let's have a nice, civil discussion for once without derailing into an insipid Caliber War.

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Shooting Comfort is bilateral.

I have always been a fan of the .45ACP round. Many stories from WWII vets when I was a kid no doubt sparked this. CQB in the Pacific Theatre esp. Modern ammo loads are much more robust than the original loads. Critical Duty +P, Corbon, Buffalo Bore all make hotter loads. Hard to beat a GI 1911 with 8 rds. of hard ball, kind of says USA USA USA!! My 2 cents.

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No baby we aint

I'm only posting because I'm first on the scene. I've outgrown caliber wars on gun forums years ago. So not that I ever needed a "defense" reason to want or keep a handgun, I've hardly needed anyone's reason.

So then, why do I like .45 ACP? Well, I'm about the handgun more than the chambering. If I love the handgun and it's chambered in .45 ACP, then I'm chasing a .45 ACP I guess, but not because it's a .45.

I like .45 because I have lots and lots of brass and it's a friendly cartridge to hand load. I have more handguns in .22LR and I have 3 times as many in 9mm, but my .45's are accurate and enjoyable to shoot.

I find that when the handgun is a similar model (or same), I can shoot a .45 more accurately than a 9mm.

While I certainly do carry a gun for personal defense and I practice with it, I am NOT a gunfighter. Thus, 95% of my guns are for pure enjoyment. I don't chase calibers for terminal performance.

Harry:

Don't get out much. Do ya?

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S&W Accumulator

30 Characters are insufficient.
However, when subject and predicate agree, they become 31 characters, spaces included. Perhaps more fitting might be the less pretentious but still correct "30 Characters are not enough."

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Formerly Model520Fan

45 GOOD FOR NOTHING? Don't even say it in jest. That is one cage you DO NOT want to rattle. I don't think anyone is saying it does not work, & well. Facts are facts, 16 beats 8, lighter wt ='s a person can carry more rounds, cheaper cost is a VERY REAL issue when arming 1,000's. Lower recoil meaning "many" can shoot it more accurately. I'm glad I only have to think about 1 person & I have 2-22's, 1-380, 2-38's, 2-357's, 1-9mm, 1-40, 1-45, AT THE MOMENT. MY 24/7 CC GUN is a 32, often/both CC is a 38 or 40, nightstand gun is (full sized) currently a 45, it was a 9mm for a LONG TIME???

Which one do You prefer to be shot in the chest with, 45 ACP or 44 MAG. Which one ( I'm now trying to write this using the word punk without getting zinged by the Mods so I will just close.)

Here's the dirty secret on the .45 ACP: it's a solution in search of a problem. Has been since before 1911.

The story is told about the Moros in the Philippines. How the .38 revolvers wouldn't stop the determined Moros. So they came up with the .45 ACP (original Browning spec was 200 grains at 950 fps; Army changed it to 230 grains at 850). And that solved the problem, no?

No. They never tell the sequel to the story: .45 didn't stop those Moros any better than .38 did. A lot of Moros weren't stopped by .30-40 Krag hits.

History repeated itself 80 years later. .40 S&W was invented because 9mm wouldn't stop determined Crooks. But .40 doesn't stop Crooks any better than 9mm. Another solution in search of a problem.

And the Europeans and everybody else says, Look at those Americans. We've known all along that Nine is all you need.

Having said all that, I love the .45. Been loading and shooting it for 40 years. It's low pressure, therefore easy on the cases and the gun. The big cases and bullets are easy to handle. It's slow so there's less tendency to lead the bore.

But it (and the .40) don't do a thing that 9 can't do better.


BOTTOM LINE:

At the range, I'm shooting .45.

On the street, I'm packing 9mm.

If one is restricted to non expanding bullets, the bigger the bore and the duller the face the better. Ball to ball there is no comparison, 45 ACP is superior to other auto loader choices by large margins. We tell people "don't use non expanding bullets in this day and age unless you shoot low power 38 Special/380 ACP or less", and there is good value in this, but the 45 ACP ball at least has an impressive history of success. A big, dull, ugly crushy bullet that punches deep and gets to the heart of the matter, it has a sterling reputation for effectiveness even without expanding bullets. As I've read here and elsewhere "a 9mm may expand, but a 45 doens't shrink". If non expanding bullets are imposed the 45 ACP is a shining star.

45 ACP enjoys improvements in effectiveness with modern hollow points, its performance is superior to 9mm Luger and others. Less energy is used to expand a large diameter bullet to the same size as a smaller caliber would, also weight and sectional density play a role in helping the 45 ACP JHP's punch deep consistently while expanding well. Looking at performance in the overall, maximum expansion as well as total expansion and final expanded shape the 45 ACP still shines. One can argue if having a larger expanded bullet helps that much, but the 45 can outexpand other calibers for what its worth. I say the greater advantage is that even with massive expansion its the greater penetration that makes it valuable in expanding bullets, it punches deep dependably. Its a consistent high performer here, always a solid choice.

The other factor in hollow point ammunition goes back to concepts of ball performance, insomuch that expanding bullets sometimes fail to expand, especially when barriers are involved. Even if smaller calibers have an easier time penetrating some barriers because of less frontal surface area and shape helping to decrease resistance, JHP have an extremely high rate of failure to expand after hitting many types of barriers in real life gun fights. Here again, the 45 doesn't shrink and will be of potentially superior damage to the target behind the barrier. What things it can penetrate it still can hurt well.

To more of OP's "stick to 45 only" its a solid choice with a sterling real life reputation that extends from its earliest days and simplist bullets all the way to today with modern bullet advancements. It penetrates deep, always crushes tissue decently at a minimum, a good bone breaker, offers high end expanding bullet performance in terms of both expansion and more importantly penetration. In every regard its a solid, strong performer with no weaknesses. It enjoys solid performance in suppressed weapons, high terminal performance and energy at reduced velocities. its well at home at 950fps or less, still offers decent performance at low velocity.

Despite all the attacks on it, despite claims it can be replaced, no one has ever been able to make a solid argument that it isn't effective and a good choice.

I enjoy shooting the .45 ACP more than any other round and I also like my pistols that fire it, such as my S&W 4506, S&W 457, M&P 45c and a M&P 45 Shield to name a few. It is very easy and fun to shoot. Also it is the only handgun round that I load. Sevens stated above, it is a very easy round to load. As someone else said, there is just something about the .45 ACP that says USA, unlike the 9mm; although I do have a few more 9's. In closing the .45 is AMERICAN like Harley-Davidson is AMERICAN: They are both big, loud and slow and I love them both!

The 45 Auto is hard to beat when it comes to penetrating barriers. Which may or may not be important to some.

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Life Is A Gift. Defend it!

Many reports of .45 ACP ball knocking down lightly-built japs during the Pacific.

One well documented case, though it may have occurred later in Vietnam I can’t remember, was one Marine or Soldier was in a rice patty (yeah I think it was Vietnam now) and was ambushed by three enemy. He pulled his Colt’s M1911A1 .45 and with a single shot each, dropped each enemy with authoritude.

He later said that if he were armed with a lesser gun, namely a 9mm, he would have been dead. Time has shown in theater that 9mm ball has next to 0 stopping power on an aggressive indoctrinated foe, while the .45 even with hardball will drop them almost every time.

And as far as modern hollowpoints go, the same advances touted for the 9mm have also occurred with the mighty .45 Automatic Colt’s Pistol. True you do give up some capacity vs. a 9mm gun, but with so many failures to stop with the “Tiny-9” it more than makes up for it in sheer knock-down dropping factor.

Just my $0.02.

With good placement a 22 caliber can kill you. Who in their right mind would volunteer for that?

ANYONE who has shot 100-150 pound deer with a 1 oz shotgun slug & the deer may not even move, can tell you, THAT IS FANTASY. An animal, or person may fall over or down if a solid bone is hit, that's NOT knockdown. The guy in Vietnam was speculating WHAT MAY OR MAY NOT HAVE HAPPENED. I just watched a video yesterday of a cop in a shootout. He drilled the bad guy center mass with a 40 caliber & even after rewinding & watching in slo-mo you cant even see the guy flinch, he went on & killed the cop.

The .45 ACP is the best semiauto cartridge for bowling pin shooting.
It doesn't recoil so much that it can't be shot fast and the 230 grain
bullets get the pins moving off the table. Of course, as Rich Davis wrote, you have to hit "the white part" of the pin (the middle.)

I have shot pins with the .41 Magnum as well. It takes them down
with more authority but I often end up needing a seventh round and
not having it when using the .41.

The old .45 is also one of the easiest cartridges to reload, and to make
accurate loads for.

Where it shines? Suppressing...

The venerable .45ACP has long been called "America's cartridge". Cool, right?

There you go, the main advantage of the .45ACP.

Hey, I'm a longtime .45ACP shooter. I still own 9 pistols chambered in .45ACP, and I only own 10 pistols combined chambered in 9 & .40.

I carried a couple issued .45's on-duty over the years, but also carried issued 9's and .40's, and more of them over the years since I carried an issued revolver.

I like my .45's. A lot. Always have.

I own a Blackhawk Convertible with .45ACP & .45Colt cylinders. (I prefer shooting it with the .45Colt cylinder, as the .45Colt has a lot more potential for loadings, going back to my handloader days.) Shooting the Blackhawk with the ACP cylinder seems a little anticlimactic, by comparison.

The .45ACP's recoil is more of a slower push and mild muzzle whip, but it's more than many shooters care to shoot, especially trying to control it in rapid fire situations. Newtonian physics wins out in such things.

The pistols made for .45ACP can become a bit less tolerant of both shooter and ammunition influences the smaller they become, too. This can cause some frustration for some shooters when it leads to an increased potential for some types of functioning issues.

The older a .45ACP shooter may become, the more annoying or painful the .45's heavier (albeit slower dwell time) recoil may become, especially if repetitive stress injuries like "tennis elbow" may be involved, or even arthritis. It's not exactly uncommon for aging heavy caliber revolver and pistol shooters to discover they can shoot 9's more easily and with less aggravation and pain. I've heard my fair share of longtime .45ACP aficionados acknowledge they've changed over to shooting more 9's than their beloved .45's because of the reduced recoil and lessened pain.

Hey, some enthusiasts just like to look at the chunky fat .45ACP bullets and think they "look effective". (I kid you not.)

As far as the increased momentum of the mighty .45ACP slapping small steel plates or bowling pins off a table? Uh, walk up and gently slap one of them with the palm of your hand and watch them fly off the table even faster and farther. People may indeed fall down for some gunshot wounds, but not because of "knock down power".

I like .45's, but I don't carry them quite as often anymore. Why? Because they're generally larger, thicker and heavier than my 9's, .40's or .38SPL's, and sometimes that matters to me as I go about my various activities.

Suit yourself.

Oh yeah, when the .45ACP became an option for the guys and gals to carry at my former agency, it was chosen by close to 70% of the people (the other option was initially, .40, and then 9mm was added back into the mix).

Once those guys and gals started having to shoot and qualify with the .45's, a line started forming of people wanting to trade the .45's for lighter recoiling and more easily controllable calibers. The demand for 9's started to increase ... even among some of the longtime instructor staff who were .45ACP enthusiasts and shooters. Why? Because the 9's were lighter and a bit thinner on the belt, easier and faster to control in shot strings and they could carry more rounds for the same number of magazines. As a piece of LE safety/work equipment (meaning duty weapon), the 9 has some nice attributes.

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Ret LE Firearms inst & armorer

It's my favorite cartridge in my favorite guns.


This is an excerpt from the original "FBI Notes" regarding the switch to 10mm (and later 40S&W). They rated the 45ACP as a close second to the 10mm...it was rejected only due to a lack of capacity at the time.
FBI & 10mm

Bonded hollowpoints/+P have narrowed the gap considerably in 9mm and I have a few 9mm's as well as a 40S&W. I have room for 'em all.

... and the US Army didn't develop a new .45 caliber rifle because of 30-40 Krag failures.

The .38's were doing just fine from the .36 Navy Colts up until the .38 Long Colt; then the U.S. became involved in the Philippine insurrection.

The Moro engagements are what started our discussions that continue up until today. The British had similar failures with the .303. They didn't adopt a new rifle chambering a .45 caliber cartridge; they improved the .303. Some Brits were apparently not totally satisfied with the performance of their .455 revolvers against determined opponents swinging large edged weapons; judging from the efforts of some to obtain .577 Howdah handguns.

The bottom line is that we have a lot of anecdotes but nothing that scientifically proves a discernible difference in the effectiveness between the common service handgun calibers.

A physically large cartridge like .45ACP is not necessary to achieve the desired results. Its size only impedes the effort to design more compact firearms and because of that, it has become obsolescent.

Both 9mms and .45 ACPs live around here. Love the guns chambered for both.

Never really believed in the 9mm cartridge though. Weird because I love the .38 Special (if I can select the load used) and the two cartridges are really much the same. Haven't been sold on the notion that 9mm bullet design improvements truly close any perceived gaps between 9mm and everything else to which it is favorably compared. It's only the 9mm fan who stridently repeats that notion about the "great strides in 9mm bullet improvements." Nobody else in Forum-land ever seems to make mention of it. Guess no strides have been made to improve any other bullet diameter sold.

Do believe in the .45 ACP. It has "presence" with diameter and bullet weight to back it up. I still believe in bullet weight, even here in 2019.

Never really believed that the Krag cartridge failed to put down the Moro Juramentados, just as I never believed in all the Korean War tales of inadequate penetration of enemy winter clothing by the .30 Carbine. Sounds more like a lot of missing was going on or else only very poor hits.

Lots of stuff gets repeated, both in print and especially out here in Forum-land until it takes on a life of its own and becomes "gospel."

We had a guy in my American Legion post who had served as a medical attendant during WW2. Not too rear echelon as his unit was surrounded for a while during the Battle of the Bulge. He commented one time that he had help patch several people up who had taken a burst from a MP40 but couldn't remember anyone making it who had taken a burst with a Thompson or M3. I'm sure he worked on more American soldiers that German but he had an interesting collection of German collar insignia from former patients.

I had little use for the 45acp until I discovered you could shoot them out of revolvers with moon clips.

They make really big holes so easy to see where you are hitting. Not much recoil when shot out of an N frame..not too loud...inexpensive..easy to find..VERY accurate..it does it all. Moon clips make for easy reloads.(I like Ezmoons..cuz they are EZ to use..)

What's not to like about the 45ACP???

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The .45 leaves a bigger hole in paper targets than the 9mm. Thus it is easier to see your hits and that in turn makes it more fun at the range for elderly gentlemen.
The 9mm is cheaper to shoot, and easier on the wrist, that makes it more pleasurable to shoot for the younger , softer generation.
Other than that, either cartridge can be tweaked to be more effective than the other.

I'll keep my scientific explanation on the 45acp brief; "Me likey"

I enjoy shooting and loading for several calibers but the 45 is by far my favorite. Loads easy, shoots smooth and accurate and makes big holes. Two world wars won should prove its effectiveness. A good friend of mine who's job is ballistic studies for police departments gave me a good comparison one time when we were discussing calibers. He said, "getting hit with a 9mm is like getting hit with a 90 mph baseball, getting hit with a 45 is like getting hit with a 75 mph bowling ball". Neither sounded pleasant to me.

I'd much rather reload 45 ACP ammo than 9x19 ammo and I have and continue to reload both. The 45 ACP has a bigger case, bigger primers, and bigger bullets, making it easier to handle them. That bigger bullet also makes a bigger hole in the target, which is much easier to see without magnification. So, is the 45 ACP worth nothing? If you think so, send all of your 45 ACP stuff, including firearms, to me.

The 9mm's of olde lacked penetration depth when expanded properly. Nowadays they have both, even in some non +P varieties. The differences between the common service calibers are down to literally fractions of an inch of expansion on paper. I frankly like to match the gun and cartridge rather than care about agency justifications or dogmatic beliefs about "stopping power."

My obsolete guns are still some of my favorites to shoot and carry.

If folks worried less about caliber and more about anatomy and shot placement everyone would be more secure.

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LEX ET ORDO

....is slightly more effective than the other common calibers, but it still takes at least 2 shots on average to stop a determined perp. Not me. I'd fall down if I felt the breeze of a bullet going by.

In a situation where there are multiple targets (a minority of the time for us civilians interested only in SD) the smaller calibers have an edge in capacity. But if you are in a situation such as police or military, you are going to have spare mags at the ready, as could a prepared civilian.

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"He was kinda funny lookin'"

My edc and night stand weapons are 45's. I believe my ears are more apt to forgive me using the lower pressure round especially if fired indoors. For what its worth.

An issue that will probable never be resolved,.... but tats ok too. Carry whichever caliber YOU are the most comfortable with and shoot well. From my readings the Moro's,.. a rather fanatical bunch of lads seemed to be calmed best with the 97 Winchester with Buckshot. Not sure if accurate but that is what I have read.

I have three .45 ACP handguns, two are 1911s and one is a S&W M1917. What’s the .45 ACP good for? It’s just a fun cartridge to shoot-more push than snap. And, as others have said, because of the size of its components it’s easy to reload. Finally, I like history and the .45 ACP is a great historical cartridge.

I recently watched a series on Netflix on training Churchill’s spies. The series took several people from different walks of today’s life and put them through the same saboteur training the Brits used in WWII. During the handgun training part they used 1911s instead of P35s or German handguns. It was interesting and entertaining to watch a grandma theater teacher hip shooting with a 1911! (Note: she did very well-as did the very petite scientific analyst!)

We’ve had this .38/9mm vs .44/.45 since the adoption of revolvers. Another member mentioned that the Army was satisfied with .36 cal Colt’s blackpowder pistols-and they certainly used them. But the standard US Army caliber from the adoption of revolvers until the late 1890s was either a .44 or .45 beginning with the Walker .44 through the 1860 Army and the SAA. Even the Scholfield’s were a .45 Colt “light” cartridge, but still a .45. My opinion is that when smokeless powder was developed and ballistic performance increased over the old BP loads, pistol cartridge developers explored using the same formula as rifle cartridge developers found effective—faster reduced caliber bullets of 150gr at 2700 FPS are flatter shooting and more effective than the .45-70 round. But at handgun distances in those early smokeless powder development days the BP .45 Colt was still more effective. The .45 ACP is pretty much the 1900 standard .45 Colt blackpowder round “modernized” (for 1910) into a smokeless powder round and adapted for a semi automatic pistol. Because of smokeless powder the case volume of the .45 Colt isn’t needed, so reduce the case substantially while keeping the same ballistics. Plus remember that we still had cavalry in 1911. The .45 ACP is more effective to humanely dispatch a 900 pound wounded or injured horse.

Yes, I like my three ACPs as well as my two .45 Colt handguns.

As a sidebar: yes, by 1910 smokeless powder cartridge development was making the .303 obsolete. Smokeless powder ballistic development at the turn of the 20th century was rapid, like communication technology today. By 1910 the Brits we’re developing a .276 round to replace the .303. And their P1914 rifle in .276, basically our M1917, was to replace the SMLE. But WWI put paid to that. Not a good idea to roll out a whole new rifle/cartridge in the second year of a world war. And by war’s end there were huge stocks of SMLEs and .303 so no sense in changing then either.

As to the .45ACP being too large and impeding the design of smaller lighter firearms, seven or eight .45s weigh about the same as fifteen 9mms. The trade off is simply more 9mms for the weight It’s only when you reduce the payload to seven or eight 9mms that you see any weight savings. As far as pistol size, the overall size difference for small .45s and small 9mms is minimal. But I’m not a fan of small handguns-just personal preference- from the sales figures I think I’m in the minority. I really don’t care for anything smaller than a Commander/Sig P6/CZ PCR sized handgun so caliber becomes a matter of what I like to shoot, not what fits in the weapon.

Speaking as a shooter and reloader, the .45acp is very easy to reload and shoots extremely well with cast lead bullets. I recently reloaded my 25,000th .45 and have enjoyed it for over 40 years.

I shoot a lot of 9mm lately as factory ammo is cheap and I don't have to bother with the cases or reloading. I have typically reloaded 9 with fmj rounds.

I carry daily and I carry a Smith 669 as I think the 9mm is equal to the .45 and I like the idea of a DA auto with a safety. I also have a Smith 457, but the 9 holds more rounds.

Why the .45 ACP? Because it launches flying ashtrays! Flying ashtrays make bigger holes and bigger holes bleed faster!!

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Stupid games = Stupid prizes.

45 handguns don't like me, because it seems I am structurally unsuited to them. Shooting 45 ACP and Colt, from a 1911 and SAA platform, both created an uncomfortable vibration pulse in my arm.

When I'm at the range shooting my S&W 1911 I pull the trigger, the gun goes BOOM, the slide goes clackity clack and then you hear the "ping" when the bullet hits the 25 yard plate. I like that. It's not just one big b-o-o-m where all you hear is the gun going off. Same thing when shooting the model 64-everything nice and sedate. almost like in slow motion. I enjoy that.
I'm past the point of dumping magazines of 9mm just to see how fast I can do it-but I must confess I do like the occasional dumping a 30 from my choppa or my mini 14 holding it at waist level screaming "die you filthy swine" or words to that effect(when nobody is looking of course )

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Forum consigliere

I like the .45 because it is a low pressure cartridge that is easy to load, and is accurate. It can be used for every purpose from defense to target shooting.

It is also the most common chambering for the best semi-auto pistol ever made, the 1911. Likewise, it works well for the entire range from defense to bullseye.

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Common sense isn't so common.

I like to punch holes in paper with a 1911 45 but carry a plastic 9mm.

YUP, 45 acp's work well whether fired from a semi OR REVOLVER. IMO several calibers using heavy, large flat meplat, bullets moving slow work best. After much use, each pin is weighted down & has a different balance & sweet spot to hit.

.45 needs longer barrel than 9mm to reliably expand hollow points.
I would rather have a jagged expanded hole with good penetration, than a smooth .45 size hole with excessive penetration.
For me, 9mm with short 3- 3.5 inch barrels. 45 a.c.p. with 4-4.5" in. barrels.

My anecdotal experience has shown me the following, as far as efficacy on the street:

1. 12 gauge 00 Buck
2. .357 Magnum 125 grain SJHP
3. .45 ACP 230 grain JHP

Then all the rest... .40 S&W, 9mm, .38 Special. I have to add a caveat about the .38 Special. The +P 158 grain SWC-HP was effective when used in a full size K-frame.

And I'm basing this on what the LEO's used on the bad guys. Bad guy on bad guy counts and doesn't count. There was never any consistency to their madness.

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I believe in the wadcutter.

Carried one for two tours in RVN and saw what it can do! Since then I have been carrying one in one form or another. My wife carries a Kimber Ultra in 45 and she loves it. To me it does what it was designed for and that was stopping people, granted its not a perfect round but keep it in its limit and it will doo the job!

I've found the 45ACP is good for punching a hole in the bottom of a used 55Gal drum so it'll drain, when preparing to use it for a burn barrel.

Do not, I repeat, DO NOT bend town below the mouth of the barrel to pop off the round without ears expecting the barrel to muffle the noise and deflect it up away from you.

I like the flying garbage can effect.

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That's just somebody talkin.

My viewpoint is a result of a sorta roundabout experience.....
I was involved in an OIS years ago - duty weapon was a S&W M66 4" loaded with the issued duty round - .38 Spl. 125 gr. JHP +P (S&W-brand ammo, so that dates me).
It took six (6) rounds to stop the subject assaulting me - all COM hits and the last in the CNS.

How different is the .38 +P from the 9mm?
I later saw all the recovered bullets from the autopsy. They were all perfectly expanded (except the 6th round, which did fragment), could have been in any ad.

Yes, I'm sure many advancements have been made in bullet design.
But as already opined - a .45 does not shrink and has sheer mass in it's favor.
Let's just say that when I left CONUS last year to work for half the year in an armed position - a M&P .45 is what went with me.

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Ret'd LEO
SWCA #2275

45ACP is the only round I've used in anger. It worked very well in 230 G hardball. I can only guess modern JHP's will work better.

.45 ACP: What is it good for?
- Reliable ones go bang
Uh...
- Bowling pin shoots
- Mis-calibrated falling steel targets
Uh...

...That's all I can think of at the moment.

More than 40 years ago I knew a LEO who was in a gunfight with 2 assailants - the one with a 9mm hit him first with 2 rounds (1 in the arm and 1 in the mid-section) then the one with a 45 hit him once in the lower leg. He said he didn't initially think the 9mm hit him, but when the 45 hit him, he went down instantly. He was saved by his partner who got both shooters with a 6 shot 38 Spl.

In my opinion the advantage of a 9mm is that when you are being shot at it is comforting to have 12-16 shots without reloading (spray and pray).

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6/23/2022

Insufficient information from which to draw conclusions. What ammo was used? Did the torso shot hit any vital organs? Did the shot into the arm strike bone or just muscle? Did the shot into the lower leg strike bone? What organs were struck by the six rounds of 38 Special? So many questions here it would take a pretty detailed analysis to draw an accurate conclusion.