The 9mm vs 45 ACP Debate: A Visual Aid...

[K_Mac]

It is the argument that I find laughable! With the differences as small as they are, there really isn't much point. I really like shooting .45 pistols and if that was my only choice I would carry the one that I worked best for me. I choose 9 mm because I am consistently more accurate when shooting quickly. I do like that I can carry an extra round or two, but that is a secondary feature.

Lohman446, even though you are only carrying 7 rounds if you were being attacked by an armed bad guy, you would shoot to stop the attacker before he stops you. Speed and accuracy are far more important than caliber.

EDIT: I am carrying 10+1 but I ain't that good!

 

[Mike_Fontenot]

"Two other effects: (1) deforming the bullet and (2) creating that much discussed temporary cavity."

Yes, deforming the bullet does require some energy, but it's not energy that gets stored in the bullet ... it just shows up as heat.

Some energy does go into creating the temporary cavity, but that energy is returned when the temporary cavity springs back (if there is no permanent damage). It ultimately turns up as heat.

From what I've learned from close-range handgun hunters (particularly 10mm and .44mag close-range handgun hunters), they typically see LOTS of permanent tissue damage, far larger than can be explained by the diameter of the expanded bullet.

 

[mavracer]

Yes, and you can prove that via simulation.

It may make absolutely no difference in any one encounter, or in any of several. But it might make all the difference in others.

Oh the irony lol.

That the exact same argument on both sides of the coin.

 

[Sharkbite]

Old Marksman pretty well summed up my response

then look up the US army's research that lead them to choose the.45 over the current .38 caliber handgun.

The Moros in the Philippines?...talk about outdated data points!!!! The same is true of the Fackler research. Lots of flaws in that data as well.

With CURRENT state of the art bullet designs, there is NO difference in wound tracts in REAL humans shot with "service calibers".

That was most noticeably RESEARCHED and DOCUMENTED in the latest FBI white paper on wound ballistics. Read it...that is the most current and extensive work on the subject. Not using data that is LITERALLY 100years old.

 

[CDW4ME]

And using your times, with your Glock 19, your assailant might be hit 5 times somewhere while he moves for an interval of one second. With the Ed Brown .45, four shots. That one shot difference could make all the difference.

That data I had handy was a couple years ago, when I was mid 40's; I've never been quick anyway and I'm only getting slower.

OldMarksman

is making me consider my 19C for carry.

I typically go for higher KE and or larger diameter (357 Sig, 10mm, 45) hoping it will cause at least a temporary incapacitation allowing me to place more shots and or get away (increase distance); I realize that attacker has up to 10 seconds of voluntary action even after a lethal hit (heart) which clouds the choice. More bullets are better, less recoil is better, more KE is better, larger diameters is better.... difficult to decide which package is "best".

 

[Lohman446]

How many shooters are skilled and trained enough that that one extra round is really going to count? I get the idea shoot until the threat stops but it's not a mantra I want to make too much of. I know it's not what you mean but it is easy to confuse with spray and pray

 

[K_Mac]

How many shooters are skilled and trained enough that that one extra round is really going to count? I get the idea shoot until the threat stops but it's not a mantra I want to make too much of. I know it's not what you mean but it is easy to confuse with spray and pray

The question really is how many shooters are skilled enough to make that one extra round count, and that is a good question. I don't know the answer, but I know that is the reason I practice and train. I am not interested in how fast I can shoot. My goal is to shoot as fast as I possibly can while maintaining combat accuracy. That is very different than an untrained and undisciplined magazine dump.

 

[marine6680]

The extra round isn't there for a "skilled user" as it were... Having extra rounds hedges your bets if you are less skilled.

More chances/tries as it were.


Though it should be the goal of all to be more skilled, and practice often.

I would rather have an extra round for just in case than a bit more power in each bullet.

 

[OldMarksman]

How many shooters are skilled and trained enough that that one extra round is really going to count?

What does that mean?

I get the idea shoot until the threat stops but it's not a mantra I want to make too much of. I know it's not what you mean but it is easy to confuse with spray and pray

And what does that mean?

 

[Lohman446]

This magic factor that 9MM meets (I'm still not certain if that is energy, bullet weight, penetration, or expanded diameter) according to these in depth studies that some of you seem to be intensely aware of:

Are those out of service length barrels or can I expect the same from shorter barrels? What is the barrel cut off length where it no longer applies? For instance if it is attained from a 2" barrel could I not attain the same thing with a 5" barrel and a .380 and thus get even less recoil?

 

[zincwarrior]

How many shooters are skilled and trained enough that that one extra round is really going to count? I get the idea shoot until the threat stops but it's not a mantra I want to make too much of. I know it's not what you mean but it is easy to confuse with spray and pray

I'm confused. You're confident that one round will stop the threat? That seems to go against police and FBI studies concerning police shoots. I believe the NYPD found typically only one in three even hit and it took two to three to stop a subject.

While I practice regularly, I would not presume to be better than the police in my accuracy and ability to stop a BG should that terrible day arrive.

I will note also, we had a stalker. We were told by the a police LT (one she had worked with) that the wife should practice and be able to quickly empty the mag to stop this particular threat, and NOT assume the the threat would stop until she did so-aka keep shooting until the threat stops, don't assume one or two shots will do it, be ready to empty the mag, and be ready to fight once you've emptied the mag on the assumption he's still coming.

 

[Lohman446]

I'm confused. You're confident that one round will stop the threat? That seems to go against police and FBI studies concerning police shoots. I believe the NYPD found typically only one in three even hit and it took two to three to stop a subject.

While I practice regularly, I would not presume to be better than the police in my accuracy and ability to stop a BG should that terrible day arrive.

I will note also, we had a stalker. We were told by the a police LT (one she had worked with) that the wife should practice and be able to quickly empty the mag to stop this particular threat, and NOT assume the the threat would stop until she did so-aka keep shooting until the threat stops, don't assume one or two shots will do it, be ready to empty the mag, and be ready to fight once you've emptied the mag on the assumption he's still coming.

No. However the argument seems to be that 1 more (of 9MM) is better than one less (of .45 / .40 / 10MM / .357 / any reasonable handgun (not counting the .460 for instance)).

Since the lowest capacity of the above is 5 we are discussing at least six shots - though when comparing a 9MM to a .40 we are likely discussing 13 or 14. While I get this is not the argument intended to be made you can see how it is easily perceived as this and turned into a "fire everything you have as quickly as you can"

But the argument is not, it seems, intended to be capacity. Its a couple tenths of a second of controlled fire between shooting 4 or 5 rounds or wherever the goal post needs to be set at the time to make the argument. The difference is not incredible. Regardless the argument for 9MM requires me to see this difference as paramount but other differences (energy, expanded diameter, weight) of similar proportion as meaningless.

Mavracer sums it up best:

Oh the irony lol.

That the exact same argument on both sides of the coin.

I'm not even sure the conclusion that 9MM is the best choice for most people today is incorrect. I think it may very well be the best choice for most people with some caveats involving expected threat etc. The argument that is being made that hinges on a fairly minor difference in time over a fairly long string of shots (5?) while insisting other minor differences are inconsequential is a poor logical argument. The fact that it hinges on some undeclared factor of the 9MM being as effective as other options seems like something the CDC would do if allowed to consider "gun" violence. Is this limited to 9MM in duty length arms or is it just any 9MM - even out of say a Bonds deringer?

 

[Rifletom]

Wow! Busy thread. A 9mm may expand. But, a .45 will never shrink.

 

[OldMarksman]

But the argument is not, it seems, intended to be capacity. Its a couple tenths of a second of controlled fire between shooting 4 or 5 rounds or wherever the goal post needs to be set at the time to make the argument.

Almost.

The issue is how many rounds will likely hit the attacker timely, and that can be affected by speed of controlled fire.

But the purpose is not to "make the argument". The purpose is to assess the likely effectiveness.

Regardless the argument for 9MM requires me to see this difference as paramount but other differences (energy, expanded diameter, weight) of similar proportion as meaningless.

"See" what you like, but consider that the recent ascendancy of the 9 with the latest premium ammunition for civilian concealed carry and for law enforcement has been brought about because of extensive testing and evaluation by a large number of professionals.

The differences in energy and weight are meaningless, except to the extent that they result in a difference in penetration. And there is only so much penetration that can be useful against a human attacker.

The difference in expanded diameter is not meaningless, but it is not very great, either. It can prove beneficial in two ways:

1. by causing more damage to one of those small critical internal body parts that a defender needs to damage; and
2. by increasing the likelihood that any one bullet will strike somethig critcal rather than miss it.

The difference between the expanded diameters of the 147 grain 9 mm and the 185 grain .45 discussed in the OP is less than 12%. The difference in cross sectional area is 25%.

Lest one assess those proportional differences as great, consider that the dimensional differences have to be considered in the context of the size an adult human chest--not that of a round squirrel.

It does not take a lot of analytical capability to realize that the difference is just not all that material.

It takes even less to realize that a second hit would be far more meaningful than those slight dimensional differences...

...and that where that hit would be meaningful is in the likelihood of hitting something critical.

It boils down to probabilities. How often will a defender hit anything critical with one shot? How often would the defender be able to get of a second controlled shot, or a third? How often would those additional hits prove effective?

I bought a .45 some years ago. Bigger bullet, and all that. Then someone opened a thread similar to what this one has become, and with some objective data to look at, I switched to a 9 MM.

Rob Pincus carried .45, and he changed to a .40. At some point, technological advances led him to start carrying a 9 MM.

Large numbers of others have been putting away their .40 caliber handguns and switching to 9 MM firearms.

I skipped the .40.

Back to the OP's question. On the rare occasions on which I carry the .45, I carry 185 grain bullets. I have a four inch barrel. I have not put extensive thought into the choice.

 

[Lohman446]

So what is the magic number in penetration? And if the goal only revolves around that number would not a .380 out of a full length barrel be able to reach that if a 9MM out of a short barrel does? If this is the case and recoil is of such paramount importance wouldn't those carrying full size pistols be better served with a full size .380 or even a full size .32?

And are we discussing 2:1 hits in 9MM vs ??

 

[OldMarksman]

So what is the magic number in penetration?

Haven't we been over that?

And if the goal only revolves around that number would not a .380 out of a full length barrel be able to reach that if a 9MM out of a short barrel does?

No.

If this is the case and recoil is of such paramount importance wouldn't those carrying full size pistols be better served with a full size .380 or even a full size .32?

It is not the case, but that does bring up a point. Shooting a very small and light 9MM pistol rapidly and effectively is very difficult if not practically impossible, and there's the matter of getting enough practice without tendon and nerve damage. If one does need to carry a very small pistol, a .380 may be better.

Generally speaking, however, there are few knowledgeable people who recommend caring a .380, and fewer who recommend a .32 these days.

And are we discussing 2:1 hits in 9MM vs ??

No. We are discussing the likelihood of being able to score more hits on a target that is moving fast before it is too late.

Faster controlled fire increases that likelihood, and lower recoil helps increase the rapidity of controlled fire.

The first time I attended a good advanced defensive pistol shooting course I took a .45--steel frame, but Officers' size. It was very clear that the shooters who brought full-size service 9MM pistols all had a distinct advantage over me.

Everything is a compromise, and while I haven't tried it, I would not be at all surprised to find that a skilled shooter with a full size steel-framed 1911 with a good trigger could outperform one with a subcompact 9 MM by quite a noticeable margin.

 

[Tactical Jackalope]

Oldmarksman is making me consider my 19C for carry.

I typically go for higher KE and or larger diameter (357 Sig, 10mm, 45) hoping it will cause at least a temporary incapacitation allowing me to place more shots and or get away (increase distance); I realize that attacker has up to 10 seconds of voluntary action even after a lethal hit (heart) which clouds the choice. More bullets are better, less recoil is better, more KE is better, larger diameters is better.... difficult to decide which package is "best".

Oldmarksman is so on point with his posts lately, I feel I don't even have to comment anymore. But I'd be the guy in person saying "amen" after every response he gives.

Also, the 19 is great. The 19C? I'd reconsider. At least get a normal barrel for it.

I do a lot of shooting from retention and then extended if the drill asks for it. The powder burns and flash from that compensation isn't pleasant.

 

[CDW4ME]

Also, the 19 is great. The 19C? I'd reconsider. At least get a normal barrel for it.

I do a lot of shooting from retention and then extended if the drill asks for it. The powder burns and flash from that compensation isn't pleasant.

The porting is advantageous for reducing muzzle flip.
I carry appendix IWB, given the presence of important (to me) and irreplaceable parts nearby ... shooting from retention - nope.

Today, I decided to shoot several guns and compare subjectively the ease / quickness of getting two rounds onto a 6'' circle at 6-7 yards.
I shot each pistol two rounds (double tap), then move to the next.

I was easily quickest with the Glock 19C and 19 with extended ported barrel.
Close behind was my Glock 23C and 23 with extended ported barrel.
Noticeably slower was my Glock 21SF and 30SF that had an extended ported barrel.

I would be content to carry either the 19C/19 with extended ported barrel or the 23C/23 with extended ported barrel.
Factory porting reduces muzzle flip the greatest, but reduces velocity.
Extended ported barrel reduces muzzle flip and increases velocity.

Chrono averages from previous sessions:
Glock 19c:
Golden Saber 124 gr. +P @ 1,126 fps
Glock 19 stock barrel:
HST 147 gr. +P @ 1,035 fps
Remington Golden Saber 124 +P @ 1,131 fps
HST 124 +P @ 1,200 fps
Glock 19 Lone Wolf extended ported barrel:
HST 147 gr. +P @ 1,068 fps
Remington Golden Saber 124 +P @ 1,150 fps
HST 124 +P @ 1,223 fps

Glock 23c:
HST 180 @ 968 fps
Ranger T 165 @ 1,082 fps
Glock 23 stock barrel:
Ranger T 165 gr. @ 1,139 fps
Gold Dot 180 gr. @ 953 fps
Glock 23 Lone Wolf extended ported barrel:
Ranger T 165 gr. @ 1,186 fps
Gold Dot 180 gr. @ 969 fps

Looking at testing of heavy clothed gel done by Lucky Gunner:
http://www.luckygunner.com/labs/self-defense-ammo-ballistic-tests/

9mm 147 HST - 15.2'' / .61 (973 fps)
9mm 124 HST - 18.3'' / .61 (1,135 fps)
40 S&W 180 HST - 18.5'' / .72 (964 fps)
45 acp 230 HST - 14'' / .85 (822 fps)

For now, I've decided to go with the 19C / 19 extended ported barrel for maximum capacity and speed / ease of placing shots onto target.

 

[KyJim]

My rule of thumb for carrying for self-defense, more or less in order:

1. Any gun is better than no gun and a reliable gun is better than an unreliable gun.
2. A hole in the right place is better than a hole in the wrong place.
3. A bullet that penetrates adequately is better than one that doesn't.
4. A big hole is better than a small one.
5. More holes are better than fewer holes.

Everything else is just trivia.

 

[TailGator]

The difference in expanded diameter is not meaningless, but it is not very great, either. It can prove beneficial in two ways:
1. by causing more damage to one of those small critical internal body parts that a defender needs to damage; and
2. by increasing the likelihood that any one bullet will strike something critical rather than miss it.

And using the measurements in the above post, the diameter of an expanded .45 is 0.24 inches larger than an expanded 9 mm, so the radius is 0.12 inches larger. We are thus arguing about the effects of increasing our margin of error by just 1/8 of an inch.

The ability to control recoil and get back on target with follow up shots would seem to be the most critical factor in overall effectiveness in a defensive encounter.

But what the heck, carry what you want.