45ACP or 9mm.

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Kleanbore said:
A 230 grain bullet fired at at 950 fps will generate more than one and one half times the felt recoil of a 124grain bullet grain bullet fired at 1126 fps from a firearm of the same mass.

Simple physics.

If I may humbly suggest that the GENERATED recoil is not the same as the FELT recoil.

In a semiautomatic, the generated recoil is partially absorbed by
1. A stronger recoil spring
2. A heavier slide
3. The slight movement of the frame

A full size steel frame .45ACP may have a less FELT recoil when compare to a subcompact polymer frame 9mm designed for CCW.

Another example, if I am recoil sensitive and yet I like the 45 caliber, I can replace the 230 grain with a 165 grain bullet and that will drop the recoil GENERATED almost down to the 9mm level that you quoted above. Thereby I can CCW a smaller compact .45ACP yet not experiencing much more FELT recoil than the 9mm.
 
Tallball said:
I have three 9mm's and three 45's. They are all good. To me felt recoil depends on the size of the gun as much as the caliber. My subcompact 9mm bothers my hand more than my 1911.

+1. That has been my experience as well.

For HD I prefer my 357 magnum. I seen enough research to be convinced.

May I suggest other factors that may affect your decision on selecting a HD caliber?

Chances are that you will not be wearing an ear protection during a HD (lots of legal reasons of why not to). One signifcant factor is the noise of a high pressure cartridge generates. A .357 mangum generates a 40,000 psi (pounds per square inch) of chamber pressure according to SAAMI, while a 45ACP generates 21,000 psi. That is a factor of 1.9 higher for the .357 mag. The pressure level at the muzzle exit is equivalent to the sound level it generates (so a shorter barrel will generate a much higher sound level).

What I submit for your consideration is, will you blast off your ear drum if you fire a round of .357 mag inside of your house? 2 rounds? 3 rounds? until the BD is no longer a threat?

The 9mm +P fares no better as it generates a 38,500 psi chamber pressure while the 40S&W generates a 35,000 psi. It would seems that a low pressure cartridge such as the 45 ACP is better suited for HD based on this consideration.

Anther factor is the muzzle flash. If you fire a high power cartridge such as the .357 mag at night for HD, will the flash blind you temporary such that you are not able to have a good follow-up shot?

I enjoy shooting my .357 mag at the range but I have "double" ear protection plus I have a 4-inch L-frame 686. I tried a 2-inch SP-101 one time and the muzzle flash was sensational in an indoor range. But even with a "double" ear protection, my ears still ring late that night. I can't imagine firing a little .357 mag snub nose without ear protection! :eek:
 
I just like the big hole in the 45 barrel! The only 45 I own right now is a Cimarron single action frontier 45colt. I need to get another 45acp. Just because.
 
Posted by Propforce: In a semiautomatic, the generated recoil is partially absorbed by
1. A stronger recoil spring
2. A heavier slide
3. The slight movement of the frame

A full size steel frame .45ACP may have a less FELT recoil when compare to a subcompact polymer frame 9mm designed for CCW.
The recoil is the mass of the firearm times the rearward velocity, and it is the same as the mass of the bullet times the muzzle velocity plus the velocity times the mass of the other ejecta (gases and unburned propellant). It is momentum. Nothing "absorbs" that momentum.

However, a heavier firearm will be pushed back at a lower velocity than will a heavy one with the same load and barrel length. Locking mechanisms and springs, etc. will change the velocity vs. time curve. The bore axis will affect the direction of the recoil vector and how much of it is angular vs. linear. And the shape and material of the grip will affect the effects of the recoil on the shooter.

A subcompact 9 can be pretty vicious. But a service 9 will be lot easier to control in rapid fire than a service .45 of the same size, weight, and configuration.

I too find a steel .45 much more comfortable to shoot than a little polymer 9, or an Airweight .38 with defensive loads. But I do not want that much weight on my hip all day.

I have settled upon a compromise-- a 9mm with enough weight to allow me to control it, but not enough to require suspenders.

What I submit for your consideration is, will you blast off your ear drum if you fire a round of .357 mag inside of your house? 2 rounds? 3 rounds? until the BD is no longer a threat?

The 9mm +P fares no better as it generates a 38,500 psi chamber pressure while the 40S&W generates a 35,000 psi. It would seems that a low pressure cartridge such as the 45 ACP is better suited for HD based on this consideration.
That is a very good point, and it is worth repeating.

Anther factor is the muzzle flash. If you fire a high power cartridge such as the .357 mag at night for HD, will the flash blind you temporary such that you are not able to have a good follow-up shot?
That, too, is something to take into account.
 
Chances are that you will not be wearing an ear protection during a HD (lots of legal reasons of why not to). One signifcant factor is the noise of a high pressure cartridge generates. A .357 mangum generates a 40,000 psi (pounds per square inch) of chamber pressure according to SAAMI, while a 45ACP generates 21,000 psi. That is a factor of 1.9 higher for the .357 mag. The pressure level at the muzzle exit is equivalent to the sound level it generates (so a shorter barrel will generate a much higher sound level).

Peak chamber pressure is not muzzle pressure. Chamber pressure drops as the chamber expands with the bullets progress down the barrel.

Using the same powder (Power Pistol), Quickload calculates:
A 230g 45ACP producing 21000 psi when fired from a 1911 will have a muzzle pressure of ~3900psi
A 124g 9mm producing 38500 psi when fired from a 1911 will have a muzzle pressure of ~5600psi
A 158g .357 producing 35000 psi when fired from a 5" bbl will have a muzzle pressure of ~9100psi

A revolver is a different matter as the pressure at the barrel/cylinder gap is much higher and much closer to peak chamber pressure than the muzzle pressure.
 
You do know there are carriable .44 magnums now days, don't need to wear a suit and a shoulder holster like Harry Callahan did. :D

Carried by masochists not 10mm toting he-men. The only difference between those .44s and the Scandium .357s is how much pain it takes for the users to satisfy their "needs".:D

Seriously, no one should feel under-gunned if they are carrying a 9mm with high quality self-defense ammunition. With the developments in pistol bullets of the last couple of decades the only advantage in terminal ballistics as far as projectile performance the .40 and .45 have is a slim one when using non-expanding bullets and that advantage is somewhat balanced by the faster shot to shot times of a 9mm. Faster shot to shot times are important because we all tend to miss more and make less effective hits than effective hits when firing in self-defense.
 
I believe in carrying multiple calibers. Each caliber has its own merit. Personally I like the .40 and 9mm. .45 is just another round to have to stock up on, ohh boy!
 
Just back from the range, 50 rds of 9x19 and .45 ACP
out of my SW1911 and CZ 75B

IT's easier to load the fat .45 ACP into the mags.

R-
 
Sound Levels

Several years ago in a discussion about hearing protection and of some posts from people who use a .357 Magnum for home defense, I researched all of the data I could find from professional institutions. Here's what I recall:
  • On average, a .357 from a handgun puts out about four times the sound pressure of a .45 ACP.
  • A 9MM, on average, is about halfway in between.
  • I have not been able to find anything on the .38 Super.

Remember that sound pressure levels are measured in decibels--a logarithmic base 10 scale. Two decibels means a lot.

There is undoubtedly a lot of variation.

When one fires in a closed space, the sound waves are reflected from walls, floors, and ceilings repeatedly until the energy is dissipated. That greatly increases the severity and risk of injury to the shooter.

I carry at home, and my 9MM carry piece is with me all the time.

Perhaps I should change (at home), but for right now, starting today, I am going to keep the .45 handy in the bedroom to at least partially mitigate the risk.

Some well known people do keep hearing protection handy. Not a bad idea.

I suffer from the effects of severe permanent noise induced hearing loss, due to my having unwisely fired on a rifle range without protection years ago. In addition, a special assignment in a civil engineering elective class on public health engineering in 1967 exposed me to the subject of occupational and other hearing loss and to audiometry. I do not take the subject lightly.

I have thought about this off and on for quite some time. It took Propforce's post to make me do something about it.
 
Recoil is where it's going now ok.

RecoilCalculator

http://www.handloads.com/calc/recoil.asp

for those examples

Enter bullet wt. Gr........: 230....147.....124
Velocity in FPS............: 900...1100...1200
Powder Charge............: 7.0....6.0.....6.0
Weight of Firearms Lbs//: 3.0....3.0.....3.0
Calculates to
Recoil Impulse (Lbs/Sec): 1.04...0.92..0.77
Velocity- recoiling firearm:11.19.8.84 8.23
Free Recoil Energy(ft Lbs:): 5.83.3.64.3.15

Course the 1911 bore axis sits higher than some
disigns like Glocks and the CZ 75B with the slide
that is reversed - male rails on the slide and it
sits 'in' instead of "On' the frame.

R-
 
Posted by Nom de Forum: Faster shot to shot times are important because we all tend to miss more and make less effective hits than effective hits when firing in self-defense.
That's an excellent point--and there's more.

We train to shoot at "center mass", or "center chest." One has little chance of hitting, for example, that small part of a moving head that would really matter in that kind of encounter.

But even a good hit in "center mass", or even two, may have virtually no immediate effect on the attacker. We have to hit something vital.

But we do not have x-ray vision, and we do not have a complete working knowledge of the locations of all of the vital parts of the human body in our heads. Even if we did, we could not process that information and put it to effective use.

Mas Ayoob tells us that we should all have copies of Gray's Anatomy on our bookshelves.

In any event, we need to unlearn what we have seen on the silver screen--that one shot will knock someone back through a door; we need to stop confusing the boom and blast at the muzzle with wounding effectiveness; and we need to realize that what we see when we shoot water jugs is not somehow relevant to cartridge selection for self defense.

We also need to realize that, in the perspective of the size of a human being, the differences in bullet diameters are just not very material.

A good way to do that is to reflect carefully on Post #40.

And that takes us right back to

Faster shot to shot times are important...

That, and to being able to get the gun out in time, and to achieve combat accuracy, should we ever experience the gravest extreme.
 
I want to apologize as it appears my post made it on here TWICE! Sorry about that. But as long as I'm doing another post it bears mentioning that any gun one carries, when needed, is better than an empty pocket. And other than a lightening strike, there's little else that will put a person down, instantly.
 
Personally I like the .40 and 9mm. .45 is just another round to have to stock up on, ohh boy!
I prefer 9mm and .45. .40 is what I call a comprimise caliber. It is the best of 9mm and .45 rolled into one round. However, its also the worst of 9mm and .45 rolled into one round. I'll stick with one or the other.

Besides, its just another caliber to stock up on:p
 
Several years ago in a discussion about hearing protection and of some posts from people who use a .357 Magnum for home defense, I researched all of the data I could find from professional institutions. Here's what I recall:

On average, a .357 from a handgun puts out about four times the sound pressure of a .45 ACP.
A 9MM, on average, is about halfway in between.
I have not been able to find anything on the .38 Super.


Remember that sound pressure levels are measured in decibels--a logarithmic base 10 scale. Two decibels means a lot.

There is undoubtedly a lot of variation.

Depending on a number of factors, a typical .357 revolver magnum puts out between 164 and 165 decibels. About 300% or so louder (I'm tired, I may have messed up that calculation) than a 5.56 AR (around 155 to 157 db), which is plenty loud already to my ears.

EDIT: Is it just me, or does 155 to 157 db on the 5.56 seem low? I'd think it'd be like 160-ish.

I have never worn double protection (muffs and plugs) when shooting .357 magnum, but I probably will going forward. With just earmuffs rated at 27 db noise reduction, I often experience mild ringing in my ears for the rest of the day. 165 db - 27 db = ~ 133 db. That's still significantly louder than a pneumatic riveter at 4' (125 db).
 
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Yeah, I've got a S&W Model 60 3" Bbl. w/adj rear sight
after a cyllinder or two of .357 Mag, I switch to .38 Special
and the carry load is .38 Special +P 125 gr. @ 1,100 fps GDs
It's usually assigned backup/hideout duty.

R-
 
I plan to keep my Glock 21 .45acp & use it for security posts but I also plan to get a Glock 23 .40

My Gen 4 G21 shoots softer than my G23, IMO. Especially with +P rounds.

YMMV.

I tend to shoot .45 ACP a bit better than anything else and, more importantly, I'm more confident in my shot placement with .45's over pretty much anything else. So I carry .45.
 
You're preachin' to the choir.......

This.

Comparing relative performance characteristics between identical calibers is pretty easy, relatively speaking. Comparing them between different calibers is much more difficult because of the differences in their cross-sectional areas.

Anybody who discusses the differences between different calibers tends to phrase things in terms of relative positive and negative characteristics under various circumstances.

Anybody who argues the differences between different calibers tends to phrase things in absolute terms one way or the other.


;)
 
I carry both. I can make them mad with the 9, and then stop the encounter with the .45.
Just kidding.

I strongly prefer the .45, but I have enough 9s to be able to say that I don't dislike it at all.
In fact, I own more 9s than .45s.
More than twice as many, in fact (if you don't include .45 revolvers).

I've never had any more trouble putting multiple .45 slugs in the black, quickly, than I do with 9s.

Ruger SR9 has become my favorite carry piece. It's light, accurate, and as reliable as a Makarov.
 
This has probably been discussed ad nauseum, but I got in a discussion with a another person a few days ago and he was like "if you shoot someone with a 9mm, you'll just piss them off, you need to shoot them with a 45".

Right away I knew he was FOS.

People need to realize that the 45ACP is a low speed. low pressure round. Yes, it's big, but it only travels ~850fps while 9mm travels ~1300fps.

What this all translates to is the 45ACP and 9mm have roughly the same energy upon impact.

Well, the FOS guy refused to believe me, so I guess he can be in his ignorant bliss.

I own 3 45ACP pistols and 5 9mm pistols so I am not biased towards either.
Sorry but anyone using energy figures to compare cartridges like the 9mm and 45 ACP does not have a clue. Both catridges would have to be at at over 2000 fps for energy to even start to matter. Neither will produce hydrostatic shock or permanent cavitation.

Gun fights are usually up close and personal. Normally you will shoot without sights and have to shoot through someone's arms or hands that they instinctively hold up in defense. Shot placement is really iffy. You will be pulling the trigger as fast as you can. You can only take what you can get. Often that will be one shot on target. Penetration is absolutely the number one factor. Secondary is how large a hole you make with maximum expansion.

Momentum and bullet construction are what really matters when choosing a cartridge. A FMJ that penetrates an arm and still gets deep enough to hit the vitals is much better than an expanding bullet that opens up and does not reach. A bullet that expands and penetrates deep enough after hitting an obstacle is ideal.
 
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Both are good. I have both. I carry both. I'm more into 9mm because it fits into a smaller package and is easier to shoot than a similar .45 pistol while also being less expensive to shoot and the performance difference seems mostly insignificant.

But, still, both.


Depending on a number of factors, a typical .357 revolver magnum puts out between 164 and 165 decibels. About 300% or so louder (I'm tired, I may have messed up that calculation) than a 5.56 AR (around 155 to 157 db), which is plenty loud already to my ears.

EDIT: Is it just me, or does 155 to 157 db on the 5.56 seem low? I'd think it'd be like 160-ish.

I have never worn double protection (muffs and plugs) when shooting .357 magnum, but I probably will going forward. With just earmuffs rated at 27 db noise reduction, I often experience mild ringing in my ears for the rest of the day. 165 db - 27 db = ~ 133 db. That's still significantly louder than a pneumatic riveter at 4' (125 db).

A 16" carbine in 5.56 is going to be 160+ dB. More like 163-ish maybe as much as 165 db. 5.56 is loud.

If your ears range for the rest of the day you did permanent damage to your hearing. Definitely double up.

I've never had any more trouble putting multiple .45 slugs in the black, quickly, than I do with 9s.

Have you done this quantitatively with a clock/shot timer? Multiple runs, same target size requirement, same number of shots, same distance, same time limit/timed to see which is quicker?
 
Outdoors the SPL difference between a 9mm and a .45 ACP is negligible. I expect the same indoors in a large space like a Wal-Mart or big store. In the enclosed space inside my house I will reaching for a 9mm but not a pistol- I will grab my Beretta Storm 9mm carbine. It's surprising how much quieter the 9mm is out of a 16" barrel, and it has a bit more 'mustard' too.
 
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