Loading ...With the exception of religion there is perhaps no greater debate than that of the defensive handgun caliber. In this article I compare the ballistic information of 9mm Luger, 40 S&W and 45 ACP.
With the amount of opinions on handgun calibers it can be difficult to obtain solid information. After reading this article you will have valuable information about how the three common self defense calibers compare to each other.
To get the most out of the information below you should have a basic understanding of some terms, specifically energy, momentum and sectional density and velocity.
This subject is highly complicated and large amounts of information have been created on it. It is my goal to give you information on theoretical performance of the various calibers with bullets of similar construction and other factors the same, this is highly valuable for comparing calibers and loads to each other but may not translate into real world performance.
Bullet construction, weight, shot placement, physical construction and the mental makeup of the bad guy all play huge parts in how many shots and how long it will take to stop him or her (some people pass out when shot, others can stay in control for long periods of time).
Terms
Grains: A measurement of weight, there are 7,000 grains in one pound. The weight of the bullet measured in grains and is printed on boxes of factory ammunition.Energy: Measured in ft/lbs this is the kinetic energy of a bullet or how hard it hits, this number is often promoted heavily on ammunition boxes. You can calculate energy by: Energy = ((Bullet Weight * Bullet Weight) * Velocity) / 450400.
Momentum: Momentum is a product of velocity and the mass of an object, the more momentum something has the harder it is to stop it, this is why it is harder to stop a semi truck than a passenger car. You can calculate momentum by doing: (Bullet Weight / 7000) * velocity
Because momentum is a factor of both velocity AND mass this means that a heavier bullet, though traveling slower may have higher momentum and thus perform better.
Sectional Density (SD): Sectional density is essentially the bullet size to weight ratio. Bullet weight alone is not enough to calculate performance, you must also take into consideration the width of the bullet. A 180 grain bullet with a width of .401 has a higher width / weight ratio than a 180 grain bullet of .451. You can calculate sectional density by: ((Weight / 7000) / (Diameter * Diameter)
Velocity: Measured in feet-per-second (fps) this is how fast the bullet is traveling. The same ammunition will develop different velocities in different guns so the velocity printed on the box is only an estimate, in reality it is often less. You can measure the velocity of a bullet by shooting it over a Chronograph
Terminal Ballistics
Terminal ballistics is the study of the effect of a bullet on the target, in the case of self defense this is often another human or small animal such as a dog.
In a previous post titled “A primer on handgun terminal ballistics” I presented an overview of terminal ballistics; having a grasp of the information presented in that post would be helpful but is not required to benefit from this article.
Meeting the 9mm, 40 S&W and 45 ACP
The three commonly available self defense calibers are the 9mm Luger, 40 S&W, and 45 ACP. All three calibers have strengths and weaknesses and each higher passionate supporters.
9mm Luger
Often referred to as just “9mm”, the 9mm Luger was adopted by the German military in 1908 and today it is in use by police departments and militaries (including the U.S) all over the world. In the U.S. the 9mm is popular for self defense because of tame recoil, high capacity and affordable ammunition. Find out more about the 9mm Luger.
The 9mm fires bullets .355 inches in diameter, common bullet weights are: 115, 124 and 147 grains.
40 S&W
The 40 S&W was introduced in 1990 in response to a call by the F.B.I for a caliber more powerful than the 9mm Luger yet still able to fit in smaller handguns with mangeable recoil. The 40 S&W’s goal is to deliver my power than the 9mm Luger with less recoil and higher capacity than the 45 ACP. The 40 S&W has been widely adopted by police departments and federal agencies throughout the U.S. Find out more about the 40 S&W.
The 40 S&W fires bullets .401 inches in diameter, common bullet weights are: 155, 165 and 180 grains.
45 ACP
Designed by John Browning in 1905 and adopted by the military in 1911, the 45 ACP is the oldest of the common self defense calibers and fires the heaviest bullets of the three. The 45 ACP is popular among those who prefer larger, and heavier bullets. Find out more about the 45 ACP.
The 45 ACP fires bullets .451 inches in diameter, common bullet weights are: 185, 200 and 230 grains.
Down to business (ballistic comparison)
Now that you have a understanding of some terms and have met the calibers lets get to comparing the calibers. I will present energy, momentum, sectional density and velocity information for each common bullet weight in each caliber.
I will use published velocities from Speer’s Gold Dot line of ammuntion, Gold Dot ammunition is extremely popular with both law enforcement agencies and civilians. In 9mm Luger and 45 ACP I will use +p ammunition for bullet where it is available.
+p ammunition is ammunition loaded to higher pressures than the caliber originally supported, modern firearms are capable of higher pressures so +p ammunition standards have been created for the 9mm and 45 ACP. I will not use or condone using +p+ ammunition because it is not officially recognized and there is no standard (each manufacturer can define it differently).
9mm Luger
115 grain JHP
Energy: 367 ft/lb
Momentum: 19.71
Sectional Density: .130
Velocity: 1200 FPS
124 grain +P JHPEnergy: 409 ft/lb
Momentum: 21.61
Sectional Density: .141
Velocity: 1220 FPS
147 grain JHP
Energy: 316.65 ft/lb
Momentum: 20.685
Sectional Density: .167
Velocity: 985 FPS
Conclusion:
The 124 grain +p 9mm Luger load has the most momentum and the most energy, making it the most capable of the 9mm loads.
40 S&W
155 grain JHP
Energy: 475 ft/lb
Momentum: 26.01
Sectional Density: .138
Velocity: 1175 FPS
165 grain JHP
Energy: 485 ft/lb
Momentum: 27.10
Sectional Density: .147
Velocity: 1150 FPS
180 grain JHP
Energy: 387 ft/lb
Momentum: 25.32
Sectional Density: .161
Velocity: 985 FPS
Conclusion:
The 165 and 155 bullet weights should perform best in 40 S&W, the 165 grain bullet is the leader with slightly more momentum and energy. Despite being heavier the 180 grain bullet boasts both less momentum and less energy because velocity dropped faster than the heavier bullet could make up for.
45 ACP
185 grain JHP
Energy: 452 ft/lb
Momentum: 27.75
Sectional Density: .130
Velocity: 1050 FPS
200 grain +P JHP
Energy: 517.93 ft/lb
Momentum: 30.85
Sectional Density: .140
Velocity: 1080 FPS
230 grain JHP
Energy: 404 ft/lb
Momentum: 29.24
Sectional Density: .162
Velocity: 890 FPS
Conclusion:
In 45 ACP the 200 grain +p load offers the most momentum and energy, making it an excellent choice, the 230 grain JHP is the second pick because it has more momentum and higher sectional density than the 185 grain bullet.
Overall Conclusions
The heaviest bullet is not the winner for any of the three calibers (9mm, 40 S&W or 45 ACP) this is because there is a point of diminishing returns where added bullet mass decreases velocity faster than the extra weight can increase momentum.
All 40 S&W and 45 ACP loads offer significantly higher momentum than the 9mm, this is expected because they have heavier bullets.
Final Thoughts
Choosing a defensive caliber is similar to selecting a spouse. Picking the first one you come across is seldom a good idea, you should shoot each of the calibers and pick the one you like the most. Ballistic information such as I presented above is important but more so is your ability to be accurate with the caliber and to be comfortable shooting it.
Any of the above calibers are very capable of stopping an aggressor but the shooter must do his part. Each have benefits, the 9mm is cheap to shoot with low recoil and high capacity, the 40 S&W delivers more punch then the 9mm in a package that is typically smaller than the 45. The 45 delivers the most energy and momentum to the target but typically trades capacity and has higher recoil.
The 45 ACP has another benefit over the 9mm, the unexpanded 45 ACP bullet is nearly as big as a fully expanded 9mm, this means even if your bullet fails to expand it contact nearly as much tissue as a fully expanded 9mm. This is an important consideration because even with modern bullets failure to expand is still fairly common.
I carry either the 40 S&W (75%) or the 45 ACP (25%) depending on the task at hand. While the 9mm is less powerful it is still capable and I don’t exclude it from carrying, in fact my wife’s CCW is a 9mm Springfield XD.
The 9mm is the minimum caliber I recommend for use as a primary defensive handgun, the .380 ACP is extremely popular as a backup gun but it uses lighter and slower bullets than the 9mm and in my opinion sacrifices too much momentum to be considered as a primary caliber. Additionally .380 ACP pistols tend to be very small which increases felt recoil, often beyond that of the standard 9mm.
It is my hope this article has answered some of your questions and may help you refute some of the claims made by passionate but uninformed gun owners.
Related posts:
- A primer on handgun terminal ballistics
- Choosing Birdshot, Buckshot or Slugs for shotgun home defense.
- About the 40 S&W
This entry was posted on Tuesday, January 22nd, 2008 at 9:40 pm and is filed under Ballistics, Firearms. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
Very informed and unbiased.
Thanks; an excellent article. It helped me decide on my next hand gun purchase, which will now probably be a 45 ACP. Now all I have to do is choose the right weapon. My current items of primary interest are one of the Kimber models, Taurus, or the Glock. A friend (reserve cop) has also suggested a Khar. I want a 4″ barrel semi-auto. This would be purely for self defense, not competitive target shooting, and although I detest “ugly”, cost is a factor and some esthetics are preferred.
My current personal defense weapon is a S&W 342 PD in 38 Special +P, with the titanium cylinder; the light weight and higher velocity bullet makes it a real hand-spanker to shoot. Not much fun.
Any suggestions, or at least a point in the right direction.
Anyway, thanks again. I needed this article before I start talking to folks who want to SELL me something!
last week end had the chance to try a taurus millenium pro in 45acp.for the conceal carry market a very nice weapon.but due to the lack of weight from the polymer frame this gun has quite a bit of recoil.put some hydra shock jhp ammo in it and look out! for me the recoil wasnt terrible ,but in a defensive situation (one hand shooting?)i think shot placement would be difficult.
thought about magnaporting it to cut down on recoil,but taurus says this will void warrenty. i am in the market for a carry piece and $ is tight had also thought about trying to” buy american” but so far its taurus,keltec,or skyy that are in my price range. hate to do it but taurus millenium pro 111 9mm may be my choice.thanks
Alan.
Hello Bayard,
I would also recommend you consider the Springfield XD, and the S&W M&P., they are in the same price range as the Glock.
The XD has a more American grip angle, and a grip safety and has won numerous awards, the S&W M&P was introduced more recently but has had a great reception.
All of what you have said is true and very fair. I have owned all three and have reloaded for all three and shot about 30,000 of each. I chose the 9mm years ago. You have to put it in the boiler room, and if you do your part it will do its’. It’s faster recovery,for repeat shots is a plus. It’s tapered shape makes it more reliable. It’s size and weight make it more usable for small gun or high-cap applications. It’s a third the price of the other two to reload. FMJ penetration has few equals in the military handgun world. With CorBon +p it nips on the heals of .357. And, utimate scroungability. Plus, I’ve seen all the “this .45 has a beavertail and a trigger job”articles I care to. If you ever see anyone spending money on a Glock, they are almost always an idiot. Thanks for the space!!
This is a good article for someone new to shooting. However I find that .45s generally have less energy, but make up for it in bullet diameter. Also, heavier bullets have greater stability and so being greater accuracy, and their barrier penetration is better. Some rifling is in fact made for the heavier bullets in a certain caliber. And chuck landrum, GLOCKS RULE!
This is a great article, you really did your homework on this subject. I have a Beretta 92fs in 9mm, its a great gun and do like the fact that it holds 15+1 rounds but that is not the primary reason why I bought the gun, I had 9mm’s all my life I reload them myself using 115 gr. JHP XP’s, I like the way they shoot but I’m looking to upgrade to a Kimber custom II .45 acp. I know how the 9mm’s shoot, and from reading your review the 9mm is the underdog but still could hold a fight on its own. However I want something with more power and punch, like that from the .45 acp, and from reading this I feel more comfortable purchasing and carrying the .45 acp. Also, what do you think about the Kimber’s reliability and performance, I like the 1911 series, just wanted your outlook and what you think, cause you sure as hell know what you talking about, thanks bud.
Great article…good basic info and comparisons…I would recommend this report to anyone considering purchasing an auto loader.
NRA Life Member
Thanks for the info, I found it very interesting and useful.
I see a lot of comparisons between the 9mm, .40 S&W and the 45 ACP but I’ve always wondered why the 357 Sig isnt included in these comparisons. Its basically the same size as the other 3 and it uses almost the same size bullet as a 9mm. I’d like to see how the it compares to the 40 S&W and the 45 ACP.
I’ve been looking into .40 S&W and like Bayard, I too would like to hear some suggestions for which manufacturers to consider, I know the XD is pretty popular but whats your opinion on Beretta’s PX4 Storm and FNH’s FNP-40 or any other suggestions?
Thanks,
I am thinking about purchasing a pistol for home protection. I have narrowed my selection down to a DAO semi-automatic in either 40 s & w or 45 acp. I will base my final decision on which caliber will provide the most reliable and dependable feeding operation. Thanks for the feedback,
Very informative. I am saving your article for future comparisons. Still, main problem is selecting the right gun for the right caliber for a defensive ccf. Reliability,stopping power are my main considerations. I have small hands and for ccf need a light weight smaller carry gun. keeping in mind my first considerations, any ideas. I can only afford to buy this once. Any thoughts out there?
Best regards,
Response
Hello, my advice is to go to a gun show or shop and hold many different guns and find one that comfortably fits in your hands.
The S&W M&P is a very good firearm and you can adjust the grip to fit your hand (comes with 3 pieces I believe).
Some people are comfortable carrying .380 ACP but I find it a bit underpowered for humans, the smallest I would carry is 9mm.
The Keltec PF-9 is a small 9mm but has been known to have some problems with reliability.
Good article. It’s the first decent comparison I’ve read between the 3 calibers. My kids and I came to the 40 smith conclusion but didn’t run the numbers. You came to the right conclusion but kinetic energy is 1/2 MV*V. Higher velocities generate bigger numbers because the energy increases as the square of the velocity. You had energy from momentum correct as M*V. What bullet weight do you use in your .40S&W? I’ve read that many law enforcement units use the 165 grain. Do you have any experience with the 200 grain hornady or other hollow points in the 40 S&W? I understand the math but like large slow heavy bullets for up close and personal. Have just purchased a Springfield XD tactical in 40 S&W and having a hard time finding info on 200 grain loads for it.
Good Article. I shoot a sig p229 in 40sw. I love my sig. 9mm is not for me. I like the feel of shooting the 40sw. 9mm feel weak. I recently shot a 380 and thought it was a squib load. I guess you have to use what you feel comfortable with. I agree with this persons final thoughts.
I I have had extensive experience with the 9mm Luger. The top end loads being a +P rated 115 Gr. from Corbon. This load pushes out that slug at 1350 per second out of a 4-inch test barrel and produce 466 FT Pounds of energy at the muzzle. This is about on par with some of the best .45 ACP and .40 S&W loads when it comes to energy. All things considered the 9mm does this with less recoil and higher capacity in most handguns. This is the load I carry in my Glock handguns. Its is not only more pleasant to shoot than the larger caliber’s it for the most part is more accurate. According to the works of Sanow and Marshall the stopping power it produces is nearly identical, with a slight edge going to the more powerful calibers. All things being equal I think the 9mm has a lot going for it for a defensive cartridge. That being said no handgun regardless of caliber can totally be counted on to stop a determined person with one shot. In my opinion I would rather have a accurate weapon that I can fire multiple projectiles into my intended target or more easily engage multiple attackers quickly because the weapon is more controllable under combat conditions for most people. In this arena the 9mm is superior to a more powerful weapon. The 9mm has the penetration and the energy to stop a fight decisively if used within handgun limitations.
Good article, however I still can’t decide on buying an xdm 9 or 40. I currently carry an xd subcompact in 9 or an S&W airweight with 38+p ammo, depending upon where I am traveling. The reason I have been so partial to 9’s is the cost to shoot. I tend to shoot several times per month and shoot my para 9mm chambered 1911 my 22 and of course my two carry guns. 300 rounds twice a month or 9mm adds up and if it were 45’s it would be twice as expensive. I don’t believe accuaracy is a trade off for stopping power and I know if I had to spend more on the range for bullets I would probably not shoot as much. With that said, 9mm or 40 XDM any suggestions?
Hi John,
You didn’t mention if you reload or not. My cost of 40 S&W for reloads is about $6 per 50 and 9mm is about $4.50 per 50.
The 40 S&W does have significantly better ballistics than the 9mm BUT the 9mm with quality JHP ammunition is fine for self defense.
If cost is your primary concern I’d go ahead with the 9mm, as 9mm components for reloading are also cheaper than 40 or 45 ACP (which tend to be about the same).