9mm vs .45: Ballistic gelatine tests vs real life

[Hunter2011]

We have seen that some 9mm ammo virtually give the same results in ballistic gelatine than .45ACP. That means those 9mm ammo should be just as effective as a .45 in self defense situations.
Is this the case in real life?

 

[Comrade Mike]

I'll say one thing. Placement.

 

[SDGlock23]

With good placement, both will work fine. With poor placement, don't count on either to work period.

 

[David E]

We have seen that some 9mm ammo virtually give the same results in ballistic gelatine than .45ACP. That means those 9mm ammo should be just as effective as a .45 in self defense situations.
Is this the case in real life?

They "work the same?"

What 9mm bullet weighs 230 grains?

 

[Hunter2011]

They "work the same?"

What 9mm bullet weighs 230 grains?

If you look at the temporary cavitation, and penetration depth, they perform the same.
If a 1000 grain and a 50 grain bullet penetrate the same and does the same damage, why do you care what weight it is?

 

[Buzznrose]

We have seen that some 9mm ammo virtually give the same results in ballistic gelatine than .45ACP. That means those 9mm ammo should be just as effective as a .45 in self defense situations.

Is this the case in real life?

From all my research on the web about what ER docs see and deal with, there isn't a noticeable difference in the major calibers (9-40-45), all else being equal (placement/JHP vrs. JHP, etc.). And lethal placement, while it kills, depends on the individual how fast the person shot dies.

This is a great article on a real world encounter from a LEO and a scumbag looking to kill him. That .45 wasn't the show stopper many believe it to be:

http://www.policeone.com/patrol-iss...ne-cop-carries-145-rounds-of-ammo-on-the-job/

That's why we need to practice failure drills (head shots) and be able to make them if the goblin simply will not succumb...

 

[jmr40]

Go back at least 100 years and look at all of the methods of comparing the 2 rounds. When real testing and studies have been conducted the 2 are virtually the same with comparable ammo. In some studies the 45 wins by a slim margin. In others the 9mm wins by a slim margin. Same is true with all other chamberings. The difference between all of them is slim, with the 40 S&W having a slight edge over either.

This would include ballistic gel, shooting live animals, human cadavers, autopsy reports, one shot stop data research from actual shootings. I've been shooting and reading about shooting for over 40 years. I've never seen any test or research data that proves to me one is any better than the other. There is a huge difference in ammo choices.

But one thing that does matter is your confidence. If you are confident in the gun or cartridge you are carrying, you will be better with it. If a 45, or 357 mag makes you more comfortable than a 9mm, then you should use it.

 

[45_auto]

If a 1000 grain and a 50 grain bullet penetrate the same and does the same damage, why do you care what weight it is?

Because in the real world it might need to go through multiple materials, each far less homogeneous than ballistic gelatin, and still be capable of doing terminal damage to the target.

 

[mnhntr]

The great caliber debate. I have seen many gunshot wounds by both. And yet it only took one of those to make it my choice never to carry a 9mm or smaller.

 

[LeonCarr]

The 9mm costs roughly half as much to shoot as the .45, which means you can shoot twice as much for the same amount of money.

The 9mm has roughly half as much felt recoil IME as the .45 in a gun of similar size, similar construction, and similar weight.

The 9mm is just as accurate as the .45.

What all of the above means is that if you shoot a .45 well, you will shoot a 9mm better. Shot placement wins gunfights. With the modern JHP ammunition available today, there is virtually NO DIFFERENCE IN PERFORMANCE between the 9mm and the .45.

Yes, I know Jeff Cooper said the .45 is the best. I know Tom Hanks shot at a tank with one in Saving Private Ryan. I know most shooters think that the .096 thousands of an inch difference in bullet diameter is the difference between life and death in a gunfight.

All of that means nothing if you don't put the bullet into a vital area. Placement is everything.

Just my .02,
LeonCarr

 

[IBEWBULL]

Weight
Velocity
Bullet configuration
Placement
State of physical condition. IE drugged etc.

There is no magic bullet.
Know your gun / bullet capabilities.

Have your weapon close at hand , run fast hide and pray hard if not.

 

[CWL]

Caliber? Temporary cavity? Who cares? In any fight, it will ultimately depend on you, your training and your will to live.

Choose a gun + caliber. Practice, train, repeat. Develop situational awareness. Listen to that inner voice when it tells you to "don't go down that dark alley".

If you have to fight, fight to win.

Now what were we talking about?

 

[Hunter2011]

The 9mm costs roughly half as much to shoot as the .45, which means you can shoot twice as much for the same amount of money.

The 9mm has roughly half as much felt recoil IME as the .45 in a gun of similar size, similar construction, and similar weight.

The 9mm is just as accurate as the .45.

What all of the above means is that if you shoot a .45 well, you will shoot a 9mm better. Shot placement wins gunfights. With the modern JHP ammunition available today, there is virtually NO DIFFERENCE IN PERFORMANCE between the 9mm and the .45.

Yes, I know Jeff Cooper said the .45 is the best. I know Tom Hanks shot at a tank with one in Saving Private Ryan. I know most shooters think that the .096 thousands of an inch difference in bullet diameter is the difference between life and death in a gunfight.

All of that means nothing if you don't put the bullet into a vital area. Placement is everything.

Just my .02,
LeonCarr

Tend to agree with this.
You can add one more advantage for the 9mm. You have more shots for the same type of gun as well compared to 45acp.

I really want a 45ACP as my next pistol, just because I allready have a 9mm. But I can't really see why....

 

[tarosean]

what 9mm bullet weighs 230 grains?

115+115=230.

 

[Fiv3r]

It's more about platform than bullet caliber for me. I shoot an all steel full size 1911 better than any other gun I own. My 9mm may hold 17 rounds of equally effective ammo, but it doesn't do me that much good if I can only hold the 9mm to center mass while I can blast out the orange with only 8 rounds of .45apc.

Yes, I could practice more and get better at shooting the 9mm. I plan on doing that for the sake of fun. However, I already shoot the 1911 well enough to be confident in carrying it.

There will always be room in my stable for at least one .45, .40, 9mm, and .357 though.

 

[45_auto]

With the modern JHP ammunition available today, there is virtually NO DIFFERENCE IN PERFORMANCE between the 9mm and the .45.

Is there some reason that 9mm hollowpoints are more "modern" than .45 hollowpoints?

Why doesn't some manufacturer apply the same magic modern technology that makes modern 9mm hollowpoints so good to .45 hollowpoints?

 

[Zaydok Allen]

If a 45, or 357 mag makes you more comfortable than a 9mm, then you should use it.

Yep. That's why I choose .45. I am comfortable with it and shoot them well.

With good placement, both will work fine.

Correct. However....

the real world it might need to go through multiple materials, each far less homogeneous than ballistic gelatin, and still be capable of doing terminal damage to the target.

This is very true. This also brings up the fact that if a bullet fails to expand due to the hollow point getting clogged, I want a wider diameter on the unexpanded bullet to create a wider wound channel. There have been many good inovations in bullet designs and hollow points are much more apt to expand. However, many carry guns have short barrels, which can lead to reduced velocity, and a lack of expansion. So don't assume your bullet will expand, and choose your ammo carefully. Pay attention to what the test barrel length is when looking at manufacturers published velocities, along with muzzle energy, and expansion.

Develop situational awareness

^^^^^ Best defense in the world. I think alot of people forget that.

I think either one will work well, and hitting your target is the most important part. But IMO, the .45 covers more contingencies and suites me well. I shoot it well, and I think the thump of a .45 has a bit of an edge for my situation. I live in a setting where I am only likely to be confronted by one or two man or animal attackers at a time since it's a rural setting. No roving gangs or anything. The reduced capacity of a 45 is not a concern to me. If it was, I'd probably just elect to carry a larger .45 anyway because I'm good with the cartridge. So, carry what you like, and what makes you feel warm and fuzzy.

 

[DaisyCutter]

I prefer heavier projectiles because in my own empirical experience they are less prone to deflection. Gelatin, with no bones, shot at a perpendicular angle, represents the ideal. Generally the real world will be less than ideal. I've never shot a human, but I have shot various game critters. I do carry a sidearm as part of my job, because I'm employed as a sworn police officer. I prefer bigger and heavier projectiles. I'm moving from 40 to 45. The cop in the next cubicle prefers 9mm.

For me, the 9mm causes anxiety. Admittedly, it's illogical, but 9mm gives me bad dreams. It may be mis-placed, but I have more faith in the bigger calibers and I operate better when I trust my equipment.

"The 9mm has roughly half as much felt recoil IME as the .45 in a gun of similar size, similar construction, and similar weight."

According to physics, isn't recoil felt on both sides of the bullet?

If/when you have to shoot, hope for a *bang-flop*, but never expect it. Mentally prepare to adapt.

 

[481]

According to physics, isn't recoil felt on both sides of the bullet?

If/when you have to shoot, hope for a *bang-flop*, but never expect it. Mentally prepare to adapt.

Surely you aren't hoping that a bullet -9mm, or .45ACP, or otherwise- will actually knock a bad guy to the ground through sheer force of impact? The likelihood of such an event is zero.

 

[MikeJackmin]

There is more to it than temporary wound channel and depth. I'd expect a .45 hollowpoint, when open, to be quite a bit larger than an open 9mm hollowpoint. If you get the same depth of penetration with the larger bullet, you've disrupted more tissue, even if this is not apparent in the gel.

That said, does it matter? Nobody knows. Lots of people think they know, but nobody really does. It might matter some, and it might not.

 

[skoro]

My rational side recognizes that 9mm and 45acp perform roughly about the same.

My emotional side has a strong preference for the 45, maybe because of the 1911s I carried way back in my military days.

That said, my compact 9mm is a lot easier to carry than my 45, so it sees a lot more duty.

 

[wally]

According to physics, isn't recoil felt on both sides of the bullet?

Yes its true, but momentum (mass times velocity) is not very important by itself.

A .45ACP 230gr at 850 ft/s has ~28 ft-lb/s momentum. (7000gr to the lb)
A 9mm 115gr at 1200 ft/s has ~20 ft-lb/s momentum.
Each also has a recoil momentum component from the powder charge mass, but this is small enough to usually ignore for handguns, and not very different for 9mm vs. .45ACP.

What you "feel" as recoil is best described as "free recoil energy". The momentum of the bullet imparts a recoil velocity to the gun and the guns mass times that velocity squared is the "free recoil energy".

For a 2lb .45ACP pistol:

28 lb-ft/s divided by 2 lbs = 14 ft/s recoil velocity and (14*14*2)/(2*32) = ~6 ft-lbs free recoil energy. (the 32 is the gravitational constant to account for pounds force vs pounds mass, the math would be clearer in metric units)


For a 2lb 9mm pistol:
20 lb-ft/s divided by 2 = 10 ft/s recoil velocity and (10*10*2)/(2*32) = ~3 ft-lbs

Hence the claim the .45 has about twice the recoil of the 9mm


A 4 oz baseball at 90 mph is 132*0.25 = 33 ft-lb/s momentum and (132*132*.25)/(2*32) is about 68 ft-lbs energy -- we'd have little trouble catching it, which is also about the same muzzle energy of a .25ACP round which nobody would want to catch!


Beyond this, carry the most gun you can hit fast and accurately with would be my advice, but if fast follow-up shots were decisive, we'd all be carrying .22lr

 

[RussellC]

Similarly, what .45 Auto goes 1400 fps?

Russellc

 

[Lj1941]

I for reasons not known to me can shoot my 45ACP M & P better than my M & P in 9. Recoil is not a factor to me when shooting either. That said most of the time I carry my CZ 82 in 9x18 because in my hands it is my most accurate pistol of all.

 

[LeonCarr]

45 auto,

When I said "Modern JHP Ammunition" I meant ammunition manufactured to comply with the FBI Protocol in place since the FBI Miami Shootout, not that 9mm hollowpoints were more "modern" than .45 Hollowpoints. The same technology is used for all JHP projectiles, with subtle differences in the size of the hollow point cavity due to a particular cartridge's velocity. A .40 or .45 will have a larger hollowpoint cavity due to their slower velocity and larger diameter than the higher velocity 9mm.

According to Jeff Cooper's writings, you don't need hollowpoints in a .45 .

Just my .02,
LeonCarr