best 380 defense load?

[Gun-Reck]

In the middle of a gunfight, with adrenaline pumping through the roof and who knows what else going on, the real fantasy for anyone who isn't highly trained and experienced in combat tactics is thinking they're going to have the time and presence of mind to figure out, in a split-second, which part of the face/thorax/pelvic girdle is unobstructed and deliver a precision shot to that location. I'll freely admit that I'm not bad-ass enough to do that, and I'd never bet my life on my ability to do so.

Two schools of thought.

1. Spray-n-Pray.
2. Only Hits Count, and good hits count more.

In any fight - if you are not picking your targets to hit, you are in trouble and losing.

Training is the key, including dry-fire.

 

[JohnKSa]

The FBI Lateral Thoracic Cavity shot, from the 1986 Miami/Dade shootout, oft repeated.

I have read the original police reports, Ayoob's analyses, and French's book on the topic. You keep using the term, but I've not heard it before and, as I said, your posts on this thread are the only place on the internet showing search hits on "Lateral Thoracic Cavity Shot".

Also, why do you keep emphasizing that the shot was through an open window? How is that relevant to penetration specifications?

It initiated both the 12" penetration spec., and the abandonment of the 9mm and development of the FBI 10mm/.40 S&W.

All correct. I was asking about your comment that before Miami the FBI had an official penetration specification of 10". Do you have some sort of reference for that--I'd like to read more on the topic.

 

[WisBorn]

Thank you all for your responses. I would have say that 380acp has been my biggest challenge in deciding what to carry.
Lately it has been Federal Punch or Percision One Ammo for hollow points.
I have also been thinking that FMJ'S may be a better choice.

Thanks again.

 

[Pistolay]

Two schools of thought.

1. Spray-n-Pray.
2. Only Hits Count, and good hits count more.

In any fight - if you are not picking your targets to hit, you are in trouble and losing.

Training is the key, including dry-fire.

Third school of thought. Aim for center mass and shoot as quickly and accurately as you can until the threat is stopped. And be carrying rounds that will penetrate to the vital organs in less than perfect conditions.

 

[Pistolay]

Thank you all for your responses. I would have say that 380acp has been my biggest challenge in deciding what to carry.
Lately it has been Federal Punch or Percision One Ammo for hollow points.
I have also been thinking that FMJ'S may be a better choice.

If you're up for a long read, here's a very lively and interesting discussion on the topic. The user who calls himself "the Schwartz" is Charles Schwartz, author of "Quantitative Ammunition Selection." He and his formulas have been referenced on the ShootingTheBull blog, among other places. I had already started carrying FMJ in my .380s, but this solidified my thinking, since my hand and wrist issues will not allow me to run XTPs in my SIGs.

Is ball still best for .380 ACP Ammo for mouse guns?

Currently I must carry my LCP II 8-5 on a daily basis due to the NPE I am in until the end of the year. Unfortunately my P365 is just a bit too bulky. Is high quality ball ammo still the best choice for .380 mouse pistols? I am running Speer Lawman right now. I know this has been...

pistol-forum.com

 

[Gun-Reck]

Third school of thought. Aim for center mass and shoot as quickly and accurately as you can until the threat is stopped. And be carrying rounds that will penetrate to the vital organs in less than perfect conditions.

Then I would be carrying a compact Glock chambered in .40S&W, with 14 rounds of 180 gr. JHP, because that is what the FBI developed to solve that problem.

But that's not what this thread is regarding.

The .380 ACP, is generally unsuitable for that school.

Shot Placement, and the correct barrel length and bullet, makes the .380 ACP punch above its weight.

If one can't pick their target, they are under-trained and under-gunned.

 

[CDW4ME]

I expect exacting shot placement under stress, on a frontal facing unobscured target, less than 10'' penetration is fine; if you disagree you are under-trained.
In before, "nuff said"

 

[Gun-Reck]

I expect exacting shot placement under stress, on a frontal facing unobscured target, less than 10'' penetration is fine; if you disagree you are under-trained.
In before, "nuff said"

This seems to miss the point that the .380 ACP is not only a minimum Self Defense cartridge, but it is also not well suited for Service Pistol applications.

On many other posts, it is mentioned that other pistols and cartridges, such as the FBI designed .40S&W, is a far better choice for that application.

But this thread is regarding the .380 ACP.

When armed with said cartridge, it is optimized with a 3.5" barreled pistol, and the Winchester PDX1 ammunition.

And, as in a fist fight, one should choose their targets and aim for them.

And, as in fist fighting, one should practice choosing their targets, and aiming for them.

And if one can't do that?

Then they are either in need of more training, or a new defense.

But to ignore the reality of the limitations of the cartridge, especially out of a short barrel, is egregious.

Shot Placement - is what makes the .380 ACP a viable Self Defense cartridge.

 

[Pistolay]

When armed with said cartridge, it is optimized with a 3.5" barreled pistol, and the Winchester PDX1 ammunition.

Here's the PDX1 from a Bersa Thunder with a 3.5" barrel getting just over 8 inches in organic gel. Now I'm sure that every ballistics expert in America is full of it, and 8 inches is just fine for a highly trained, stone-cold operator, but this 70-year-old guy with severely compromised hands and wrists is just going to do it the way I was taught with the gun I can still handle.

.380 ACP Winchester PDX1 Ammo Gel Test

Ballistic gel test of the .380 ACP Winchester Supreme Elite Bonded PDX1, 95 gr JHP, using a diluted form of SIM-TEST Ballistic Testing Media. This format is...

www.youtube.com

 

[Gun-Reck]

... in organic gel.

SIM-TEST Ballistic Testing Media, not organic gel.

Still, very good bullet performance.

but this 70-year-old guy with severely compromised hands and wrists is just going to do it the way I was taught with the gun I can still handle.

Your choice - but your "school" is severely compromised without shot placement.

Think of a boxer, and not a "highly trained, stone-cold operator."

Learn some basic anatomy, and then dry-fire practice picking your targets and transitioning between them, in front of a full length mirror.

Otherwise, good luck.

 

[CDW4ME]

Clear gel tends to yield greater penetration than synthetic gel, with examples:
https://le.vistaoutdoor.com/wound_ballistics/load_comparison/load_comparison.aspx
Manufacturer test, Federal makes the ammo, their tests:
View attachment 1173170

How did those same bullets penetrate in Lucky Gunner clear gel?
https://www.luckygunner.com/labs/self-defense-ammo-ballistic-tests/
9mm 147 gr. HST - 19'' / .60
9mm 124 +P HST - 18.3'' / .66
40 S&W 180 HST - 18.5'' / .72

In all three examples clear gel has yielded penetration about 50% greater (approximately 6 inches) than manufacturer testing.
Apply that to your favorite 380 bullet that penetrates 10'' in clear gel - now subtract.

To follow up on my prior post about clear gel.
Clear gel tends to yield greater penetration, as in my above example with Federal HST in manufacturer tests versus Lucky Gunner clear gel tests.
To add additional examples to what I'm saying, Winchester ammo; manufacturer testing in heavy clothing versus Lucky Gunner clear gel heavy clothing.
https://winchesterle.com/-/media/Pr...gun-Bullet-Barrier-Testing-Protocol_2016.ashx
https://www.luckygunner.com/labs/self-defense-ammo-ballistic-tests/
9mm 147 gr. Ranger Bonded - 14'' in manufacturer test versus 21.5'' in clear gel
40 S&W 180 Ranger Bonded - 13.9'' in manufacturer test versus 16.9'' in clear gel
40 S&W 180 T Series - 12'' in manufacturer test versus 16.2'' in clear gel.
Those are significant differences in penetration.

Using several examples from manufacturer testing, 10'' in clear gel is likely overstating the actual penetration; 10'' in clear gel is likely not 10'' - it is less.
A very good explanation from the Lucky Gunner link above on why 12'' minimum penetration is the accepted standard:
"the 12 inch minimum penetration standard can be more confusing. If the bullet needs to reach the middle of the chest cavity where the organs are, wouldn’t we need a penetration depth less than half of that in most cases? Some of the reason for the 12 inch minimum standard is simply “playing it safe” and allowing for the possibility of attackers possessing greater than average girth. But part of the rationale is based on the simple reality of three-dimensional anatomy.

We typically imagine a potential attacker will be directly in front of us, facing our direction with squared shoulders, much like the paper and cardboard targets we usually use. But it should come as no surprise that this is not how gunfights usually go down. We have to account for a human target that may be turned slightly toward or away form us at an angle, or possibly even above or below us, or with arms partially obscuring the torso.

If you’re having a hard time picturing why this would affect the penetration depth necessary to reliably stop an attack, imagine you’ve just been ambushed by a 275 pound dude wielding a baseball bat. As he is rushing toward you, winding up the bat for a knockout blow, you manage to draw your pistol and fire a perfectly aimed shot at his upper chest. But since he’s in mid-swing, the bullet doesn’t go straight into his chest — it enters his arm just above the elbow and now has to pass through half an arm, a shoulder, a rib cage, and a lung in order to reach the heart or spine. A bullet that can penetrate only 9 inches might lodge in the guy’s rib; unpleasant for him, but not the definitive fight-stopping shot we want."

So, if we were going to select a 380 bullet based on Lucky Gunner testing, the Hornady FTX or Sig V Crown at least penetrate about 13'' and consistently expanded, in that test.
In Sim Test the Hornady penetrated 11.25'' - as with my other examples, less penetration than exhibited in clear gel:

 

[Gun-Reck]

"the 12 inch minimum penetration standard can be more confusing. If the bullet needs to reach the middle of the chest cavity where the organs are, wouldn’t we need a penetration depth less than half of that in most cases? Some of the reason for the 12 inch minimum standard is simply “playing it safe” and allowing for the possibility of attackers possessing greater than average girth. But part of the rationale is based on the simple reality of three-dimensional anatomy.

We typically imagine a potential attacker will be directly in front of us, facing our direction with squared shoulders, much like the paper and cardboard targets we usually use. But it should come as no surprise that this is not how gunfights usually go down. We have to account for a human target that may be turned slightly toward or away form us at an angle, or possibly even above or below us, or with arms partially obscuring the torso.

If you’re having a hard time picturing why this would affect the penetration depth necessary to reliably stop an attack, imagine you’ve just been ambushed by a 275 pound dude wielding a baseball bat. As he is rushing toward you, winding up the bat for a knockout blow, you manage to draw your pistol and fire a perfectly aimed shot at his upper chest. But since he’s in mid-swing, the bullet doesn’t go straight into his chest — it enters his arm just above the elbow and now has to pass through half an arm, a shoulder, a rib cage, and a lung in order to reach the heart or spine. A bullet that can penetrate only 9 inches might lodge in the guy’s rib; unpleasant for him, but not the definitive fight-stopping shot we want."

The same "Lucky Gunner" fantasy.

A large human torso is 10" thick.

The FBI spec was 10" of penetration with good expansion before the Miami/Dade 1986 shootout, where the lateral thoracic cavity shot, through an open car window, that included the upper arm, facilitated the dumping of the 9mm round, the new 12" spec., and the new .40S&W/180 gr. round to meet that new spec...

But the large human torso is still 10" thick, and all the vital targets are still within it.

And the upper arm, if a barrier, won't cover all vital shot placements.

The .380 ACP requires shot placement, and with good expansion like the Winchester PDX1 round, will transfer energy, and core an even bigger hole than most 9mm rounds.

As for the Hornady FTX? It trades away Self Defense effectiveness for Service Pistol penetration.

Shot Placement - Hits count, good hits count more.

 

[JohnKSa]

The FBI spec was 10" of penetration with good expansion before the Miami/Dade 1986 shootout...

You've stated this several times. What is your source for this claim? I would like to read more about it.

...through an open car window...

Why do you keep saying this?

First of all, why would it be relevant that the shot was through an OPEN window? How could that mean anything in terms of penetration?

Second, it was NOT through a car window at all. The shot almost certainly impacted Platt as he was crawling out of the passenger side of the Monte Carlo onto the Cutlass that was to the right of the car. His torso was already out of the car when the shot hit him. Anderson's book diagrams this on pages 37-41. There's no way he was shot through the car window since the Monte Carlo came to rest with the passenger side against a parked Cutlass. There were no FBI agents positioned to shoot across the hood of the Cutlass into the window of the Monte Carlo.

...and the new .40S&W/180 gr. round to meet that new spec...

The FBI went to the 10mm to meet the new spec., not the .40S&W. It wasn't until after the FBI had already adopted the 10mm in 1989 that the .40S&W was introduced in 1990.

 

[CDW4ME]

The same "Lucky Gunner" fantasy.

A large human torso is 10" thick.

The FBI spec was 10" of penetration with good expansion before the Miami/Dade 1986 shootout, where the lateral thoracic cavity shot, through an open car window, that included the upper arm, facilitated the dumping of the 9mm round, the new 12" spec., and the new .40S&W/180 gr. round to meet that new spec...

But the large human torso is still 10" thick, and all the vital targets are still within it.

And the upper arm, if a barrier, won't cover all vital shot placements.

The .380 ACP requires shot placement, and with good expansion like the Winchester PDX1 round, will transfer energy, and core an even bigger hole than most 9mm rounds.

As for the Hornady FTX? It trades away Self Defense effectiveness for Service Pistol penetration.

Shot Placement - Hits count, good hits count more.

Please stop quoting me and posting the same naivety.
If you are comfortable with a bullet that underpenetrates, that is on you: but to try to convince others that under penetration is acceptable is flawed.
Your opinion and referencing outdated standards are just that.
People would do well to stack the deck in their favor as much as possible and bullet performance is one variable they can try to control in advance.
Current bullet performance recommendation of at least 12'' penetration is widely accepted and few (other than you) will argue otherwise.
https://shootingthebull.net/blog/bu...ats-the-big-deal-about-12-penetration-anyway/
https://www.activeresponsetraining.net/stop-worrying-about-overpenetration
https://www.thetruthaboutguns.com/how-do-i-choose-self-defense-ammo/
"In other words, it’s the average of bone, skin, blood and muscle density. Per a conversation I had with Chris Laack, head of handgun ammunition development for Vista Outdoors (that’s who makes Federal and Speer and many more) at SHOT Show, the correlation seems to be about a 2:3 ratio. If a bullet penetrates 12 inches in gel, it will penetrate about 8 inches in a person. So bear that in mind when you look at testing results,"

I pick ammo that penetrates at least 12'' in case I do not have a unobstructed shot to the vitals.
380 is not a primary caliber for me, it is a 2nd gun (AKA "back-up") and I have Hydra-Shok deep in the 380 for the infrequent times I carry it.
There is zero chance you will convince me to carry under penetrating ammo and I think its a disservice to try to convince others that it is acceptable.

 

[481]

To follow up on my prior post about clear gel.
Clear gel tends to yield greater penetration, as in my above example with Federal HST in manufacturer tests versus Lucky Gunner clear gel tests.
To add additional examples to what I'm saying, Winchester ammo; manufacturer testing in heavy clothing versus Lucky Gunner clear gel heavy clothing.
https://winchesterle.com/-/media/Pr...gun-Bullet-Barrier-Testing-Protocol_2016.ashx
https://www.luckygunner.com/labs/self-defense-ammo-ballistic-tests/
9mm 147 gr. Ranger Bonded - 14'' in manufacturer test versus 21.5'' in clear gel
40 S&W 180 Ranger Bonded - 13.9'' in manufacturer test versus 16.9'' in clear gel
40 S&W 180 T Series - 12'' in manufacturer test versus 16.2'' in clear gel.
Those are significant differences in penetration.

Using several examples from manufacturer testing, 10'' in clear gel is likely overstating the actual penetration; 10'' in clear gel is likely not 10'' - it is less.
A very good explanation from the Lucky Gunner link above on why 12'' minimum penetration is the accepted standard:
"the 12 inch minimum penetration standard can be more confusing. If the bullet needs to reach the middle of the chest cavity where the organs are, wouldn’t we need a penetration depth less than half of that in most cases? Some of the reason for the 12 inch minimum standard is simply “playing it safe” and allowing for the possibility of attackers possessing greater than average girth. But part of the rationale is based on the simple reality of three-dimensional anatomy.

We typically imagine a potential attacker will be directly in front of us, facing our direction with squared shoulders, much like the paper and cardboard targets we usually use. But it should come as no surprise that this is not how gunfights usually go down. We have to account for a human target that may be turned slightly toward or away form us at an angle, or possibly even above or below us, or with arms partially obscuring the torso.

If you’re having a hard time picturing why this would affect the penetration depth necessary to reliably stop an attack, imagine you’ve just been ambushed by a 275 pound dude wielding a baseball bat. As he is rushing toward you, winding up the bat for a knockout blow, you manage to draw your pistol and fire a perfectly aimed shot at his upper chest. But since he’s in mid-swing, the bullet doesn’t go straight into his chest — it enters his arm just above the elbow and now has to pass through half an arm, a shoulder, a rib cage, and a lung in order to reach the heart or spine. A bullet that can penetrate only 9 inches might lodge in the guy’s rib; unpleasant for him, but not the definitive fight-stopping shot we want."

So, if we were going to select a 380 bullet based on Lucky Gunner testing, the Hornady FTX or Sig V Crown at least penetrate about 13'' and consistently expanded, in that test.
In Sim Test the Hornady penetrated 11.25'' - as with my other examples, less penetration than exhibited in clear gel:

More in support of the point(s) that you are making with regard to the Clear Ballistics Gel product is that it lacks the correct density (0.999 ≥ ρ ≤ 1.043 g/cm³) to properly drive projectile expansion resulting in an over-representation of maximum terminal penetration depth. Ultimately, projectile expansion is directly dependent upon dynamic pressure which is determined solely by the Bernoulli* equation, PDYNAMIC = ½ρV². In the specific case of the Clear Ballistics Gel product, its density, 0.824 g/cm³, falls outside of the correct range of density needed to correctly initiate and drive projectile expansion.

In almost every imaginable example that you might produce—

9mm 147 gr. Ranger Bonded - 14'' in manufacturer test versus 21.5'' in clear gel
40 S&W 180 Ranger Bonded - 13.9'' in manufacturer test versus 16.9'' in clear gel
40 S&W 180 T Series - 12'' in manufacturer test versus 16.2'' in clear gel.

—the expanded diameter of identically constructed projectiles fired into the Clear Ballistics Gel product is significantly smaller than that of those fired into shear-validated 10% ordnance gelatin; leading us right back to an over-representation of maximum terminal penetration depth.

In other words, you are claims are correct in every aspect of their content.

Finally, the Clear Ballistics Gel product fails to shear-validate in accordance with the presently accepted standard (of a .177-caliber steel BB fired from an air gun over a chronograph at 590 ± 15 fps into 10% ordnance gelatin resulting in a penetration depth of 8.50 ± 1.00 cm) that correlates to both mammalian soft tissue and 10% ordnance gelatin. That is a tremendous problem. The process of shear-validation is important because it ensures that the gelatin has the correct viscosity so that it will properly represent the viscous drag components that dominate projectile deceleration in the non-cavitation velocity regime (which is less than 750 fps for a BB). BBs are used because they are spherical; if the BB ''tumbles'', geometric uniformity is ensured because the sphere is symmetric on all axes (x, y, z) . If a test medium cannot be confirmed to behave properly in the low-velocity regime, then that test medium cannot be expected to reliably and accurately duplicate projectile performance as it would occur in mammalian soft tissues.

*Note: Bernoulli's equation, proposed in Hydrodynamica written in 1738, has withstood the test of time. I think that it rests on pretty solid ground 285 years later having never been disproved.

 

[CDW4ME]

@481

 

[Pistolay]

SIM-TEST Ballistic Testing Media, not organic gel.

Still, very good bullet performance.



Your choice - but your "school" is severely compromised without shot placement.

Think of a boxer, and not a "highly trained, stone-cold operator."

Learn some basic anatomy, and then dry-fire practice picking your targets and transitioning between them, in front of a full length mirror.

Otherwise, good luck.

SIM-TEST media IS organic. It's made from animal protein.

And the 8.25 inches of penetration in that test is NOT good bullet performance. It's terrible performance. The PDX1 in .380 is a poor-performing round, and I seriously doubt you could find a ballistics expert who would agree that it's "very good bullet performance."

As far as lecturing me on my supposed inadequacies, your time would be better spent worrying about yourself if you actually believe that your skills are so awesome that you don't need a bullet with adequate penetration.

 

[Gun-Reck]

Please stop quoting me and posting the same naivety.
If you are comfortable with a bullet that underpenetrates, that is on you: but to try to convince others that under penetration is acceptable is flawed.
Your opinion and referencing outdated standards are just that.

You are basing your "under penetration" on the current Service Pistol Spec., which the .380 ACP is not.

And I am simply expressing Facts, including the one that to FBI dumped the 9mm and tailor-made the .40S&W/180 gr. to meet that spec..

The 10" torso, and the ability of the Winchester PDX1 round to hit any target within that torso, is a fact as well.

Shot Placement - Hits count, good hits count more.

 

[Gun-Reck]

SIM-TEST media IS organic. It's made from animal protein.

And the 8.25 inches of penetration in that test is NOT good bullet performance. It's terrible performance. The PDX1 in .380 is a poor-performing round, and I seriously doubt you could find a ballistics expert who would agree that it's "very good bullet performance."

As far as lecturing me on my supposed inadequacies, your time would be better spent worrying about yourself if you actually believe that your skills are so awesome that you don't need a bullet with adequate penetration.

What target, in a 10" torso, will the round fail to hit, while expanding larger than most 9mm rounds?

Shoot what you want.

I like big holes in vital organs, and train accordingly.

 

[Gun-Reck]

Why do you keep saying this?

What percentage of Self Defense shootings are through an open window of a car, resulting in a lateral thoracic shot, including the upper arm, like the FBI Miami/Dade 1986 shootout?

As opposed to a "give me your wallet" frontal or oblique presentation.

That Service Pistol spec., is nicely fulfilled by the FBI's .40S&W/180 gr..

For the .380 ACP, it's Shot Placement.

 

[JohnKSa]

What percentage of Self Defense shootings are through an open window of a car...

1. It's totally irrelevant since any loading will penetrate an OPEN window without any loss of performance.
2. It's totally irrelevant since the shot you are talking about did NOT go through a window. Platt's torso was out of the car when that round hit him.

Now, to the issue of the upper arm getting in the way of a self-defense shot. I don't know that there's any data that would allow us to quantify the percentage, but it's quite common for people to twist around before being shot. This can result in attackers actually being shot in the back because they twist away when they see the gun. It's not a stretch to assume that if they didn't quite twist far enough that the shot might hit them in the arm before going into the chest from the side.

The idea that all self-defense shots go into an attacker who is facing them directly so that the necessary penetration is minimized is absolutely incorrect.

What target, in a 10" torso, will the round fail to hit, while expanding larger than most 9mm rounds?

You desperately need to watch some bodycam/dashcam/security cam video of shootings. Attackers get shot from all angles, not just straight in through the front of the torso. I've seen one where the attacker was running away with his torso twisted slightly toward the victim while holding his gun out and shooting more or less backwards at the victim. Since he was still shooting at the victim, he still posed a deadly threat and returning fire would be justified and very important to stop the threat.

In addition, it's not uncommon for attackers to get hit in the hands and arms since their hands and arms tend to be out in front of their torsos while wielding a gun or contact weapon.

I'm not saying this to prove that the .380ACP is worthless for self-defense, but it's important to understand that self-defense shots come in all different varieties, NOT just straight in shots from a target standing up and facing the victim.

And I am simply expressing Facts, including the one that to FBI dumped the 9mm and tailor-made the .40S&W/180 gr. to meet that spec..

I like facts.
Fact: The 9mm was just one of the rounds that the FBI approved for carry prior to the switch to 10mm. In fact, agents at the Miami shootout shot both 9mm and .38Spl and possibly the .357Mag. The change wasn't a switch from 9mm to 10mm, it was a switch from pretty much everything they had issued before to the 10mm.
Fact: The FBI didn't tailor-make the .40S&W. They tailor-made a 180gr 10mm loading. AFTER the FBI adopted the 10mm, S&W introduced the .40S&W to duplicate the downloaded FBI 10mm ammo.
Fact: FBI adopted the 10mm in 1989.
Fact: .40S&W was introduced in 1990.
Fact: FBI first issued .40S&W pistols in 1997.

By the way, here's another interesting fact. The 1076 10mm issue pistol was problematic and so, before the FBI switched to the .40S&W in 1997, for awhile they issued SIG pistols in 9mm. Which means that the timeline actually goes like this:

1988 FBI develops the 10mm FBI loading.
1989 FBI officially switches to 10mm.
May 1990 FBI begins issuing S&W 1076 pistols in 10mm.
May 1991 S&W 1076 pistols are recalled.
1991 FBI begins issuing SIG pistols in 9mm.
1997 FBI issues pistols in .40S&W.

 

[bsms]

I'm not a cop or the FBI (thank goodness). When I was in the military, I carried an M9. And a rifle. But I'm long retired and Arizona isn't Iraq or Afghanistan. I almost always carry either my S&W 38, Glock 42 (380) or Glock 27 (40 S&W). In the extremely unlikely event that I need to shoot, my #1 goal is taking at least one bad guy with me. #2 goal is surviving, but I accept that if I as a civilian pull a gun, it already means things are not going my way and survival may no longer be an option. Hence goal #1 - If it is my time to meet Jesus, I want to bring along at least one fellow with me.

Does that mean I'm not the meanest, toughest dude on Medicare out on the streets? Yep.

In 380, I used to use FMJ. Now I use copper bullets in my 380 & 38. Penetration will be pretty good and if any additional damage happens, OK. If I can conceal it, the Glock 27. I feel a bit overarmed with 9 rounds of 40 S&W. But that isn't a bad feeling and I'm comfortable shooting it one handed or two.

Does everyone think my way? Nope. And they don't have to. Carry whatever one is willing to carry. I avoid cities, being out late at night, etc. The tack & feed store and the hardware store are my main destinations and surprisingly few gangs of thugs go to either. And if I die? Well, I'm on Medicare already and if I give a good account of myself, I'll be content. YMMV.

 

[CDW4ME]

The 12" Penetration spec. is the FBI's answer to the Lateral Thoracic Cavity shot (upper arm + >1/2 chest, with 3 clothing layers).

Even a large torso is <10" front to back, with 1 clothing layer.

So, for a self-defense round, 10" penetration through heavy clothing, with reliable expansion, is fine.

Like Winchester's 95 gr. PDX1 load, from a 3.5" barrel.

This heavy clothing test is from a sub 3" barrel, expanded reliably, and would still hit vitals:

​

(Note: a Ka-Bar combat fighting knife - has a 7" blade.)

You are basing your "under penetration" on the current Service Pistol Spec., which the .380 ACP is not.

And I am simply expressing Facts, including the one that to FBI dumped the 9mm and tailor-made the .40S&W/180 gr. to meet that spec..

The 10" torso, and the ability of the Winchester PDX1 round to hit any target within that torso, is a fact as well.

Shot Placement - Hits count, good hits count more.

You posted a video where the 380 Winchester penetrated 8.3''
Yet you keep referencing 10'' in clear gel.
8.3'' is the more accurate reflection of penetration.
Now apply that to what I posted before:
"In other words, it’s the average of bone, skin, blood and muscle density. Per a conversation I had with Chris Laack, head of handgun ammunition development for Vista Outdoors (that’s who makes Federal and Speer and many more) at SHOT Show, the correlation seems to be about a 2:3 ratio. If a bullet penetrates 12 inches in gel, it will penetrate about 8 inches in a person. So bear that in mind when you look at testing results,"
Using 8.3'' which you posted in the video yet subsequently ignore, that is more like 6'' in tissue.

You may not get a frontal facing, unobscured shot to the vitals; that is a fact.
You can't shouldn't assume good shot placement in a dynamic situation; well, if one rejects realistic possibilities they might.
One will be trying to make hits before getting injured or killed themself; there may be more than one attacker.
If the attacker has a knife, or other weapon in hand, the vitals may be obscured.
Not everyone is small stature.

What variables can we pick in advance? Caliber, capacity, bullet type.
What variable is to be determined? Shot placement and that will be determined while fighting for your life.

 

[Gun-Reck]

1. It's totally irrelevant since any loading will penetrate an OPEN window without any loss of performance.
2. It's totally irrelevant since the shot you are talking about did NOT go through a window. Platt's torso was out of the car when that round hit him.

Now, to the issue of the upper arm getting in the way of a self-defense shot. I don't know that there's any data that would allow us to quantify the percentage, but it's quite common for people to twist around before being shot. This can result in attackers actually being shot in the back because they twist away when they see the gun. It's not a stretch to assume that if they didn't quite twist far enough that the shot might hit them in the arm before going into the chest from the side.

The idea that all self-defense shots go into an attacker who is facing them directly so that the necessary penetration is minimized is absolutely incorrect.

"As Platt climbed out of the passenger side car window, one of Dove's 9 mm rounds hit his right upper arm and went on to penetrate his chest, stopping an inch away from his heart."

Only the lateral upper torso/arm was presented.

How likely is that as a Self Defense situation?

The large human torso is still 10" thick. from the back as well, and a few inches wider.

https://twitter.com/Alphafox78/status/1677308184132820993​

Avoiding shooting through the upper arm, what vital organ(head/thorax/pelvic girdle) would not be hit, from any angle, by a well placed and expanded Winchester PDX1 .380 ACP round?

Fact: The FBI didn't tailor-make the .40S&W. They tailor-made a 180gr 10mm loading.

Semantics - The FBI Spec. was 10mm/180 gr./1,000 fps/400 ft-lbs... which was eventually optimized and proliferated throughout LEA's as the .40S&W/180 gr..

The intended target, would not know the difference.

 

[Jim Watson]

I have two .380s, one was my IDPA BUG when that was a side match, nothing I care to shoot all day as a main match gun. The other is largely a memento of a deceased friend.
I can find room for a subcompact 9mm as a hideout gun and don't have to puzzle over the best bullet for .380.