Pistol Caliber Guide

Primary Arms Staff

7/6/2020 1:22 pmwww.primaryarms.com

When purchasing a pistol, cartridge selection is one of your most important considerations.


Pistol cartridges come in a wide variety of shapes and sizes, and each has its own specific applications. For certain roles, such as hunting and self-defense, your caliber choice can be life-saving, so research is an absolute necessity.


Fortunately, we’ve prepared this guide to give you the basic run-down on the most common pistol calibers, so you can focus your research when searching for the best pistol caliber for your needs.


.22LR


Primary Uses: Target, Competition, Training


Major Benefits: Low Cost, Negligible Recoil


.22LR is the most common rimfire cartridge in the US. The cartridges are small, inexpensive, and low-impact, making them great for plinking and introductory marksmanship. Many Americans will get their first experience on the range while shooting .22LR rifles and pistols at summer camp.


.22LR pistols are an excellent training tool, but they are unsuitable for personal defense or hunting most game. Despite the old myth, .22LR is not more lethal because bullets ‘bounce around inside the target.’ Even if it were true, deflection off bone is a bad feature for any kind of personal defense.


Historically, rimfire cartridges like .22LR have also suffered with reliability, but modern ammunition standards have greatly improved this caliber’s performance. Paired with a reliable pistol, stoppages should be a relative rarity.




5.7x28


Primary Uses: Personal Defense, Target


Major Benefits: High Velocity, High Capacity, Low Recoil


One look at FN’s 5.7x28 cartridge, and you’ll know the difference.


5.7 cartridges are designed like miniature rifle cartridges, which leads to very unique performance features. Though the bullets are similar in weight to .22LR, they travel at speeds up to 2200fps, which is closer to rifle velocity. This speed gives them exceptional penetrative power, particularly in breaking through soft armor.


The 5.7 cartridge was designed for personal defense, and it excels in that role. The high capacity magazines and low recoil make for quick follow-up shots, while the velocity helps with terminal ballistics.


The major weaknesses of 5.7 are its rarity and price. Ammunition is somewhat scarce, and you’re not likely to find many options at a local shop. This cartridge’s performance depends heavily on the bullet design, so quality self-defense ammo will run a premium too. Since it’s a niche caliber, 5.7 pistols can also be pricy, though the new Ruger-57 pistol is bridging that gap.




.380 ACP


Primary Uses: Concealed Carry


Major Benefits: Low Recoil, Acceptable Ballistics, Common


.380 ACP is often described as the smallest acceptable personal defense cartridge, and we’re generally agree. Though .380 bullets are about 20-30% lighter than standard 9mm, perceived recoil can be reduced by over 50%.


As a result, .380 is commonly found in sub-compact pistols, where recoil is magnified by the firearm’s low weight and minimal grip surface.


Both .380 ammunition and .380 pistols are relatively common, so you should have no problem finding a setup that meets your tastes.




9mm


Primary Uses: Personal Defense, Law Enforcement, Concealed Carry, Target, Competition


Major Benefits: Most Common Pistol Caliber in US, High Versatility, Great Generalist


9mm, 9x19 Luger, and 9x19 Parabellum are synonymous with America’s most popular pistol cartridge. Not to be mistaken with the Russian 9x18, 9mm can be found in almost every gun store in the country. In most cases, you’ll find a wide variety of pistols and ammunition from all over the world, which speaks to 9mm’s prevalence. It’s the popular choice for enthusiasts and professionals alike, and its versatility cannot be understated.


9mm strikes the perfect between capacity, size, and recoil. Historically, critics have dismissed this cartridge’s terminal ballistics, but modern ammunition has eliminated any doubt with up to 3/4-inch expansion. If that isn’t enough, users can opt for +P, +P+, or 9mm NATO ammunition, which goes over standard pressure to increase the muzzle velocity. Not every 9mm pistol can handle high pressure ammunition, though, so defer to manufacturer’s guidelines on maximum specifications.


While 9mm isn’t commonly used for hunting, it dominates in most other applications, which is why we recommend it so highly. No other cartridge will offer you the same degree of freedom, though .45 ACP and .40 S&W come close. 9mm is so versatile that even rifle manufacturers are taking notice. Pistol-Caliber Carbines (PCCs) are increasingly popular in the US, and 9mm carbines are the favorite among competitors and enthusiasts alike. Not only does this provide better value to the owner, but it offers a great training tool for rifle fundamentals.




.357 Sig


Primary Uses: Law Enforcement, Personal Defense


Major Benefits: High Energy, Low Deflection, .40 S&W Conversions


.357 Sig is a unique cartridge, hybridizing .40 S&W and 9mm. Originally, .357 Sig was designed around a necked-down .40 casing with 9mm bullets, but modern .357 Sig casings are also slightly longer. The result is a high-pressure cartridge that spits out .355-caliber bullets with impressive velocity.


.357 Sig was a lot more popular in the mid-00’s, as police groups were adopting the cartridge for its penetrative performance on vehicles. Compared to 9mm, .357 Sig deflects less against glass and penetrates deeper through metal surfaces. Since police officers work from a vehicle, these features were particularly attractive at the time, though many units are moving back to 9mm for its controllability.


One additional note: .357 Sig pistols usually have a .40 S&W counterpart. You can convert most .40 S&W pistols to .357 Sig with minimal effort, which is beneficial for practice, since .357 Sig ammunition can be expensive.




.40 S&W


Primary Uses: Personal Defense, Law Enforcement


Major Benefits: Good Capacity, Wide Bullet Variety, Common


.40 S&W is seen as the middle ground between 9mm and .45ACP, but it’s actually the offspring of a much more energetic cartridge: 10mm. Back in the 80s, the FBI realized that 10mm was too powerful for some agents, so they set after a moderate cartridge. Using the same bullets as 10mm, .40 S&W offered many similar benefits without the impact of 10mm’s recoil.


Over the next decade, .40 S&W became one of the most popular cartridges for law enforcement and citizens alike. With more energy than 9mm, .40 S&W had a reputation for stopping power, supported by higher magazine capacity than the alternative .45 ACP.


.40 S&W isn’t as popular today though, as many police groups transition back to 9mm sidearms. Modern ammunition has largely nullified the ‘stopping power’ gap, and 9mm’s controllable recoil gives it added agility. Still, for those looking to buy a proven self-defense caliber, .40 is very accessible, and ammunition is available in any store.




10mm


Primary Uses: Hunting, Personal Defense


Major Benefits: Impressive Power, Wide Variety of Loadings


10mm—the nuclear option.


Jokes aside, 10mm is a powerful semi-automatic pistol caliber. Loaded to its max, 10mm delivers a similar muzzle energy to magnum cartridges and can reach velocities up to 1700fps and beyond. 10mm bullet range from 115gr to 220gr, offering an exceptional variety, which can meet most any task. Despite this power, 10mm pistols like the Glock 20 boast a full 15rd magazine capacity, which greatly exceeds most magnum calibers.


Historically, the 10mm had problems with reliability, as the impulse would damage semi-automatic pistols over time. Nowadays, these problems have been solved, making 10mm a great choice for those looking for more impact.


Due to its impressive ballistics, 10mm is a popular hunting and wilderness defense cartridge. Whether you’re hunting deer, boar, or protecting yourselves from bear, 10mm is an adequate companion for any outdoorsman. The added pressure of this round will improve its performance against dense bone and dangerous game.


If you’re new to pistols, be warned: it does have a bit of a bite. 10mm ammunition is hot, which means it kicks plenty and costs more to shoot. If you use the lower-power factory ammunition, prices are more forgiving, but you may as well be shooting a .40 S&W instead.




.45ACP


Primary Uses: Personal Defense, Law Enforcement, Target, Competition


Major Benefits: Very Common, Good Terminal Ballistics, Versatile


Rising with the prevalence of the 1911 and 1911A1, .45 ACP is the classic American semi-auto cartridge, serving with the US military for over 100 years. Though most groups have switched to 9mm, .45 ACP remains a strong favorite among American enthusiasts, so you can expect to see this cartridge for many decades to come.


Fans of .45 ACP will swear by its ballistics, and there can be no denying the facts: .45 ACP makes bigger holes than 9mm. With current hollow-point ammunition, a 230gr .45-caliber bullet can expand to a 1-inch diameter, which few pistol cartridges can beat. However, this benefit comes at the cost of recoil and capacity (or at the cost of having a very, very large handgun). To some, this may not make any difference.


Regardless of criticisms, the 1911 served soldiers well for many battles, and the design has grown more effective with modern bullet designs and new magazines. No matter where you fall in the 9mm vs .45 debate, .45 ACP is undeniably a tried and true cartridge with a lot of potential for personal defense, target shooting, and competition.




.38 Special


Primary Uses: Training,Personal Defense, Target


Major Benefits: Usable in .357 Magnum revolvers, Low Recoil, Affordable


.38 Special is one of the oldest revolver cartridges to still see common use today. Originating in the late 1800s, .38 Special is common, affordable, and easy to use. Though it lacks the power of magnum cartridges like the .357, .38 Special is plenty capable for personal defense, having seen extensive use in both in military and police applications.


Many enthusiasts choose .38 Special as a practice cartridge, since you can shoot .38 Special from most .357 Magnum revolvers. For concealed carry purposes, a .38 Special revolver will be lighter and more affordable, but if you’re just looking for a good general-purpose revolver, it’s more cost-effective to buy a .357 Magnum to shoot both .38 and .357 alike.




.357 Magnum


Primary Uses: Personal Defense, Hunting, Target


Major Benefits: High Energy, Manageable Recoil, Can Use .38 Special in .357 Revolver


While semi-automatics dominate the pistol market, revolvers do enjoy one unique benefit: magnum cartridges. The most common magnum cartridge is the .357 Magnum, which was created by Smith & Wesson in the 1930s as a response to Colt’s .38 Super. Smith & Wesson used the .38 Special cartridge as a basis for their design, using a newer powder and a longer case length, which prevents use in .38 special revolvers. The result was a nearly-identical cartridge that could achieve twice the pressure rating as the original .38 Special.


Since its inception, .357 Magnum has been a mainstay for American revolvers, seeing widespread use among both military and police groups. While revolvers have fallen out of favor, many Americans still swear by the cartridge’s effectiveness, and .357 does enjoy a few notable benefits over the weaker semi-automatic cartridges. In dense woods, .357 Magnum is an exceptional deer-hunting cartridge, and many hunters choose to carry .357 revolvers when taking game at close range.




.44 Magnum


Primary Uses: Hunting, Target


Major Benefits: Very High Energy, Common


.44 Magnum is a high-power cartridge that will command the attention of any enthusiast. Originally developed in the mid-50s, .44 Magnum had a similar development to .357, in that it stemmed from a lighter predecessor, .44 Special. Just like how .357 is longer that .38, .44 Magnum is longer than .44 Special, but that’s just a safety precaution to prevent magnum cartridges from damaging a .44 Special revolver.


That said, .44 Special isn’t as cost-effective as .38 Special, so most .44 Magnum users will stick to their full-power cartridges. Slinging 300gr projectiles at over 1300fps, .44 Magnum is a true powerhouse, making it a top choice for hunting larger game. Some would say that .44 Magnum is too powerful to be practical for self-defense, where volume of fire and shot placement are far more important than raw energy transfer.


Ignoring practicality, .44 Magnum remains one of the most iconic magnum pistol cartridges, certain to have relevance in the American market for a very long time.




Conclusion


These cartridges only make up a small selection of the available options, though they represent the common picks for most enthusiasts.


No matter which caliber you choose, bullet selection will play a huge role in your firearm’s effectiveness. Modern ammunition is changing the way we view these calibers, and though the caliber debates may never end, anyone can enjoy the variety provided by today’s market.