9mm vs .45ACP

I'm surprised the 9mm expanded to about the same diameter of the .45. Could that be the +P vs. the short barrel ammo? Have you tested +P vs +P?
 
Raimus,

In many tests, .45 Gold Dots do expand to larger sizes than 9mm. 9mm Gold Dots typically expand to .52-.58. .45 Gold Dots get into the upper .6-low .7 range. All of these are well above the hole from .45 FMJ, which has been shown to be effective.
 
It would be interesting to see if the two rounds perform equally well after passing through clothing.

Also, does a a short barrel Gold Dot perform differently when fired from a full size gun versus a short barreled gun?

Still an interesting test with somewhat surprising results, in any case.

Thanks for the post.
 
I think years back when 9&45 FMJ were all that were ever compared in ballistic testing, there was almost unanimous consent that the .45acp was the best choice for numerous reasons. However, with the tech advances 9mm ammunition, the gap (here again I think agered to by a majority) has closed the considerably allowing for one to feel confident when choosing a 9mm for defense. That being said, the fact the the U.S. Armed forces are still prohibited (I believe) from carrying anything other than FMJ in their respective M9's I must admit concerns me...
 
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The problem I have with the ballistic jello is that it is a backwards approach to a solution. The IWBA attempted to establish itself as the underwriters lab of ballistics testing and cash in. The FBI lab in conjunction with the IWBA created the "FBI protocols". The rounds with a real world effectiveness rate that is legendary 2 examples are the 115 grain+p+ 9mm jhp and the full power 125 Grain full power 357 magnum perform poorly in jello. Major law enforcement agencies such as the US Border Patrol, Texas DPS do their own ballistic testing.

A 45 will kill you stone cold dead, a felon in Gary, ind ran 200 yards after being shot thru the heart with a 230 grain HST, but, he was dead.

Why does a 38 special +p 125 grain JHP perform better in jello than the exact same bullet from a 357 Magnum? Is the 38 special a better fight stopper? I don't think so. The only difference between these loads is about 500 fps velocity. What does that velocity achieve? Even the medical community does not agree. That energy does SOMETHING or there would be no difference between the two loads.

Instead, they should have taken the best loads and used them to develop a standard test. Anyone that know anything about scientific research understands that the best laboratory is the field, however, jello junkies claim that anything that cannot be replicated in the lab is unreliable and useless. If I have to shoot someone to save me or my loved ones I don't care if it is a CNS hit, massive blood loss or extreme pain that stops the attack.

Neither the 9mm or the 45 ACP is the hammer of Thor. A handgun is a compromise. The handgun you carry is a compromise, more ammo, more power, easier to conceal, recoils less you get the point.

I do not think the answer lies in small and fast or heavy and slow, I think it lies somewhere in the middle. The reality is the projectile is such a small part of the total equation, more important is tactics, mindset, and the desire to survive. The gun itself, is merely a delivery system.
 
AMD, Read again;
17 hits from a 45...officer switched to 9mm...[Read again]
The assailant had a .45 & switched to a .380 Bersa. The officer had a 9mm. Most .45 mags doesn't carry over 8-10 rounds. So, 17 hits + misses from a .45 would be allot of clips.

Anyhoo, I have a .45 love it. But, I'm seriously considering a 10mm for my next SD pistol. Awesome round!!

Nanuk, very good post!

IMHO;
For slow bullets & Bow/arrows the answer is 'Momentum' (AKA Inertia) for penetration prediction. Momentum is 'force' vectored (It has direction).
KE is too velocity dependent for slow bullets like pistol bullets.
KE is the total energy.
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Regarding the use of gel:

It is better than many realize. .357 does GREAT in it. How about Gold Dots .357 vs denim + gel? 15" penetration, .75 expansion. That is awesome.

115gr standard pressure have done 18" pen, .52 expansion. Added energy should add, not hinder. If nothing else, it's great vs barriers.

Those are great results.


Beyond gel:

Consider gel a benchmark for initial selection. What then? When rounds fail to perform, that information gets out. 9mm Gold Dots were selected by so many LEO partly because of testing. They are STILL used because they perform.
 
For slow bullets & Bow/arrows the answer is 'Momentum' (AKA Inertia) for penetration prediction.
Click to expand...
As long as the projectiles all have similar sectional densities and don't expand, or as long as all they all expand exactly the same, this is a reasonable view of momentum.
Momentum is 'force' vectored (It has direction).
Click to expand...
Momentum = mass x velocity

We know that:
Force = mass x acceleration = mass x velocity / time

Since momentum = mass x velocity we can rewrite the equation for Force as:
Force = momentum / time

While force and momentum are clearly related, it's inaccurate to characterize momentum as "force vectored".

Momentum is equal to the product of Force and time. In other words, if you know the impact momentum of a projectile and the amount of time it takes to decelerate the projectile to a stop in the target medium, then you can calculate the force applied to the target medium by the following calculation:

Force applied to target = (impact momentum) / (time required to decelerate the projectile to a stop in the target medium)

We can sum up the relationship between force and momentum by saying the force is the rate of change of momentum with respect to time and that momentum is the result of force applied to a movable object over a given time.
KE is too velocity dependent for slow bullets like pistol bullets.
Click to expand...
Kinetic energy is just another parameter of a moving object.

If you know the impact energy of a projectile and the penetration depth into the target medium (assuming the projectile stops in the target medium), you can calculate the force applied to the target medium by:

Force applied to target = (impact energy) / (penetration distance in the target medium assuming the projectile stops in the target medium)

Basically, force is the rate of change of energy with respect to distance and energy is the result of force applied to a movable object over a given distance.

Momentum and energy are just two different ways to look at a moving object.
 
Interesting, thanks! It is appreciated.
But, movement within the 'impulse' is found direction (hopefully fwd)[maybe, 'vectored' is not the best word]. 'I only know enough, to be dangerous' as the saying goes. I mainly know about it from some research I did studying/ gaining more knowledge in archery, especially concerning light & fast arrow vs slower heavier arrows concerning penetration/potential penetration. Which opened up a great debate in archery 'Momentum vs KE. That is where I am coming from.

The formula that I have seen for Momentum is:
Mass x velocity / {weight(7000gr =1 lbs) x gravity(32.174)} = 225218. Measured in Slug-feet.

EDT:
KE= The total energy of a body in motion. It is scalar, non-directional.
 
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Arrows and bullets work in different ways

Acc371
I believe momentum to be more applicable to archery than KE.
I have had plenty of pass through shots on deer with arrows that carried a paltry 60# of KE, but about .45 momentum.

I use this formula for momentum:
projectile weight x projectile speed = _____ / 225120 = momentum

A 400 gr. arrow @ 260 fps has about .46 momentum and will pass completely through a deer (assuming a standing still broadside deer with behind the shoulder / double lung shot placement and a good broadhead)

However, I'm not so sure that momentum is the best indicator of handgun performance.

My chronographed averages for 5 shots:
230 gr. Ranger T out of a Glock 30 @ 874 fps / 390# KE / .89 momentum
125 gr. Ranger T out of a Glock 32 @ 1,340 fps / 498# KE / .74 momentum

If we determined handgun effectiveness using momentum, then the 45 acp (in that example) is clearly better (17%); however, according to KE the .357 Sig is "more powerful" (22%). :confused: :D

Edit to add additional example:
From my 16'' Stag 2T .223 using a 60 gr. Nosler Partition handload:
60 gr. @ 2,807 fps / 1,050# KE / .75 momentum :D
 
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CDW4ME
Yeah, 60# is plenty. There have been many a deer killed by a #50-60# recurve. Broadhead design plays a part too.
400gr@260fps. With a fixed blade you bet it'll pass through a deer!


I use a single blade w/ a bleeder blade. MY arrow runs around 432gr at 70#. So, I'm in the .50's.
It looks like both of us are well above the 5gr/lb minimum.

Well, 230gr vs 125gr. is like a coal truck vs sedan concerning Momentum. As an analogy I use. So, in essence a 230 gr will have more thump.
Now, If you look a the KE formula, yes, 110gr will do better. Like I said, KE is highly velocity dependent.

KE = 1/2mass x Velocity2 / 225218

If you play with the KE numbers, you can get some interesting results.
 
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Accuracy is easy when you are shooting at paper. Its quite different when you are shooting at people who are shooting back at you. I agree its important but putting big holes in the torso, cns, major bone structures does not take a gun with superb accuracy.

I have never fired a handgun that at self defense ranges, up to say 20 yards, that was not accurate enough to put the majority of rounds in the torso. This includes old cap and ball revolvers. When choosing a combat handgun accuracy is really not a concern unless the gun had some serious manufacturing defects its going to be accurate enough. Do you worry about your combat knife being accurate enough or effective enough?
 
The formula that I have seen for Momentum is:
Mass x velocity / {weight(7000gr =1 lbs) x gravity(32.174)} = 225218. Measured in Slug-feet.
Click to expand...
Right. Well, nearly right. The formula should be stated as:

Weight{grains} x velocity{fps} / (7000 x 32.174...)

We don't measure mass in the english system, we measure weight. The denominator is a couple of conversion factors required to get the units right when dealing with the english measurement system. You have to convert from from grains to lbs (divide by 7000) and then from lbs to slugs (divide by 32.1740486... . Slugs are the english system's unit of mass.

After all the conversions you have Momentum = mass{slugs} x velocity{fps}

If you do it in kilograms and meters per second you can dispense with the need for conversions since kilograms are already a measure of mass.
If we determined handgun effectiveness using momentum, then the 45 acp (in that example) is clearly better (17%); however, according to KE the .357 Sig is "more powerful".
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It's a mistake to look at either momentum or KE as a direct measure of handgun effectiveness. Neither one tells the whole story by itself, and even the two of them together still leave a lot to be desired.

In my opinion, it is not possible to find a formula that provides a single number measure of handgun effectiveness.

Momentum and energy both provide some insights into the potential of a projectile to damage/apply force to/penetrate a target medium, but there are many, many reasons a projectile might not live up to its potential and many, many reasons why even if it does, the target may not be rapidly incapacitated.
Like I said, KE is highly velocity dependent.
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It is what it is. KE is the measure of the potential of a projectile to do work (cause damage, if you will). It can be used, in combination with penetration to determine the amount of force applied to a target medium by a projectile that stops in the target medium.

It's not something that someone made up because they liked velocity, it's a scientific quantity, measuring an important parameter of a moving object, verifiable via repeatable experiments.

It doesn't tell the whole story of projectile effectiveness--not by a long shot--but the idea that it should be dismissed or discounted because the results it provides don't match popular theories of bullet effectiveness or personal opinions is extremly problematic from a scientific standpoint.

The problem isn't that it is highly velocity dependent or that it doesn't provide intuitive results, the problem is that people try to make it mean more than it really does.
 
Nice posts JohnK .... I would have attempted but I was too tired (and I would have done half as good a job as you did ;-) ).

Like it or not (and where it places your favorite round in the pecking order) KE is the ability to do damage and the higher the KE, the more total damage that will be done. Now where that damage occurs in the path of traveling through objects, clothing, upper tissue, bone, inner tissue, and possibly objects even passed the body ... that will be heavily influenced by bullet mass, size, and velocity.
 
John K,your right that; Neither formula tell the whole story. Bullet design is another important factor. FMJs & HPs are worlds apart in expansion, damage & penetration. Toss in a few other factors like Sectional density, etc.

Also, about desired effect/rapid incapacity expectations. Many factors like like like adrenaline, Endorphins & illicit drugs are another factor.

Yes, KE is widely used in determining penetration potential. Especially in the firearms & archery industries.

Your last statement is also true.

I'll just leave KE vs Momentum debate as it is.

Very well written.
 
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...the higher the KE, the more total damage that will be done.
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That's exactly correct as long as the bullets expend all their energy in the target medium. To make it accurate in the general case I'd modify it slightly to say "the higher the KE, the higher the potential for damage."

Of course, "higher potential for damage" and "more total damage" are relative terms. For perspective, on the low end of the energy spectrum, a service pistol caliber on average, might damage a couple of ounces of tissue. On the high end of the energy spectrum, maybe 3 ounces.
Also, about desired effect/rapid incapacity expectations. Many factors like like like adrenaline, Endorphins & illicit drugs are another factor.
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Right, once you start talking about incapacitation instead of damage to the target medium, things get extremely complicated.

Based on the FBI wound volume testing results, a typical service caliber handgun bullet destroys about 0.1% of a 180lb human. Obviously, losing a few oz of tissue won't cause someone to stop attacking unless those few oz of tissue are part of something very important and the attacker is incapacited, or unless the attacker gets scared and decides to voluntarily stop attacking.
 
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