Ammunition Demystifier

Ammunition - a word filled with mystery. When I began my journey into firearms, this subject and the overwhelming confusion that it created was almost enough to stop me in my tracks! I am one of those people that just dives in and consumes information relentlessly until I capture from it what I need, and I was beyond confused. What I have come to understand is that it IS confusing! As a woman, I am not incapable, in any sense of the word, of figuring it out, (which was what I started thinking when I began researching ammunition!) what I am however is practical. I want to know what I need to know and what it means for me, for my firearms and for my safety. I will try here to demystify and bring into clarity, the basics of what you need to know in regard to defensive ammunitions, .380, 9mm, .38 Special, .357 Magnum, .40, .45 calibers. There are many other calibers than what will be discussed here so I have provided links on the bottom of the page for those who would like to go deeper into this subject.

IMPORTANT

Using the wrong ammunition in your firearm is extremely dangerous. You must know the proper ammunition for your firearm. The owners manual that comes with your firearm will tell you exactly which ammunition is safe for your firearm to shoot. Many manufacturers make the manuals available online as well.

Let's start with some basics

THE DEFINITION OF AMMUNITION:

Ammunition: the projectiles with their fuses, propelling charges, or primers fired from firearms

THE BASIC COMPONENTS OF AMMUNITION

The basic components of ammunition are the case, primer, powder, and projectile(s). Shotshells have an additional component called wad.

Case: The container that holds all the other ammunition components together. It's usually made of brass, steel,copper, paper, or plastic.
Primer: An explosive chemical compound that ignites the gunpowder when struck by a firing pin.Primer may be placed either in the rim of the case (rimfire) or in the center of the base of the case (centerfire).
Gunpowder: A chemical mixture that burns very rapidly and converts to an expanding gas when ignited. Modern smokeless powder will burn slowly when ignited in the open (outside of the case). Black powder is less stable and can be explosive when ignited in the open.
Projectile: The object(s) expelled from the barrel. A bullet is a lead projectile fired through a rifle or handgun barrel. A slug is a lead projectile fired through a shotgun barrel. Shot is a group of lead, steel, tungsten, or bismuth pellets fired through a shotgun barrel.
Wad: A seal made of paper or plastic separating the powder from the slug or shot in a shotshell. The wad prevents gas from escaping through the shot and holds the shot together as it passes through the barrel.

IMPORTANT TERMS AND DEFINITIONS

Round or Cartridge: The correct and accurate name(s) for the "entire package". It is not accurate to use the word bullet, as the bullet is one of multiple components.

Bullet: The bullet is actually just the pointed top or tip that you typically think of when you picture a round. A shotgun round does not have an actual "bullet" inside. It has either buckshot, a lot of little round pieces or a "slug" which is shaped like a bullet.

Caliber: 1) The diameter of a bullet or other projectile, 2) the diameter of a bore of a firearm usually expressed in hundredths or thousandths of an inch and typically written as a decimal fraction, i.e. .380 caliber, .45 caliber, sometimes in the metric scale i.e.. 9mm. It is important to performance that a bullet should closely match the diameter of a barrel to ensure a good seal.

Gauge: The term "gauge" describes bore diameter of a shotgun, but unlike "caliber" used for handguns and rifles, the larger the number, the smaller the bore.

Centerfire Ammunition: Ammunition in which the primer is located in a small cup in the bottom center of the case.

Rimfire Ammunition: Ammunition in which the primer is located in the bottom rim of the case. Typically, rimfire rounds are smaller calibers than centerfire rounds.

Hollowpoint: A metal jacketed cartridge design with a concavity in its nose to increase expansion on penetration of a solid target. Some hollow-points are also designed to fragment as they expand. They are least likely to over-penetrate the target and harm an innocent bystander. Commonly used for self-defense

Softpoint: A metal jacketed cartridge design in which the nose of the core of the bullet is exposed to ensure the expansion of the bullet upon impact. Often abbreviated "JSP" or "SP." They tend to expand more slowly than a Hollow Point bullet and are used where deeper penetration and expansion are needed.

+P or +P+ Ammunition

"Plus P" or "Plus P Plus" mean that the cartridge is loaded with a higher pressure than standard ammunition. This gives your round more firing power and a greater impact on your target.You can see whether or not your ammo is +P or +P+ on the cartridge box, or sometimes it's stamped on the base of the cartridge. +P or +P+ cartridges are usually center-fire cartridges.

Grain

Grain is the actual weight measurement of the bullet component of a cartridge, not the entire cartridge. The more it weighs, the more grain it has. Standard weight for .45 ACP ball ammunition (full metal jacket - FMJ) is 230 grain. Standard for 9mm is around 115 grain.

Note: There are many inconsistencies in ammunition manufacturing so this number does not always reflect the actual diameter of the bullet and in some cases the metric scale is used. In some cases a second number is given usually representing the bullets length and letters (abbreviations or words) will then follow to complete the name of the cartridge. This entire "name" is important and you will need to know the entire description, including the letters.

What Is FMJ, JSP, JHP?

Yes, sometimes letters are added to the name to differentiate and describe rounds. These letters describe how the round is "packaged". Every minute detail of a round effects how it performs, so naturally in what and how a round is packaged matters in how it will perform. I did tell you it was complicated, but no too complicated. I promise you will get it and will be able to approach a shelf of ammunition with confidence!

FMJ is "Full Metal Jacket" and is used to describe rounds that are entirely encased (except for the bullet base, typically) in a metal jacket, usually copper alloy called gilding metal. FMJ rounds are considered standard and sometimes referred to as "ball". Generally these rounds are designed with little to no expansion in mind. Which means that the bullet will maintain its circumference during and after penetrating the target. They are comparatively inexpensive, feed well and give good penetration in most materials.

JSP is "Jacketed Soft Point" and is used to describe rounds that are encased in a metal jacket, again, usually copper alloy called gilding metal, but leave the soft lead core exposed at the tip of the bullet. The soft nose deforms upon striking dense mediums, and these rounds are generally designed to expand rapidly at the nose and mushroom, ensuring that the center of gravity stays in front, and causing the bullet to continue traveling forward through the target. The larger frontal surface area causes more tissue disruption compared to most non-expanding bullets.

JHP is "Jacketed Hollow Point" and is used to describe rounds that are encased in a metal jacket, usually copper alloy called gilding metal, but have a small cavity in the nose along with a round opening in the jacket in the nose. JHP rounds are also designed for expansion but tend to have faster "mushrooming" effects because the hollow point is filled with high-pressure material when the bullet impacts, often peeling back the jacket and making a "mushroom" shaped projectile.

WHAT HAPPENS WHEN A ROUND IS FIRED?

Let's look at the anatomy of a round and what happens when it is fired. Killeen Bishop describes it in her article "Ammunition 101."

"Looking at a cartridge from top to bottom, your first layer is the bullet. That's what leaves the gun towards your target when you pull the trigger (assuming all goes well). The next layer is your powder charge. This is the part that actually is quickly ignited by the next layer of the bullet. The very bottom of your cartridge, usually the round shape at the base, is your primer. Primers can be ignited by striking the outside of that round shape or right on the inside of the round base, depending on whether or not it's rim-fire or center-fire ammo. What happens when you fire a gun is that the firing pin inside the gun hits the rim or center fire. This causes an ignition of the powder inside the casing, which causes the bullet to propel forward towards your target and the casing to expel out the ejection port. This is how the casings end up landing all around, and sometimes even down your shirt. Since the casings have housed the fiery dance between the primer and the powder, they are inevitably hot, thus, you don't want them to land down the front of your shirt and nest. ;) Don't worry ladies. I've even seen some men do the "hot casing line dance", too. It does happen and for the most part you don't have any control over them with the exception of what kind of clothing, hat, and eye protection you wear to inhibit the rogue piece of hot brass."

What Rounds Do You Need For Your Handgun?

That depends on the caliber of your firearm along with the rounds recommended by the manufacturer. The calibers listed below certainly are not all of them, but will give you an overview of each of the most popular and recommended calibers for personal self defense. As the .22, .25 ACP and .32 calibers are common, they are generally not considered powerful for self defense, so are not addressed here. Much of the information and images used here were supplied by Genitron, where you will find complete listings for all caliber rounds.

.380 Automatic

The .380 Automatic was introduced by FN of Belgium about 1912 and was designed by John Browning. One reason for the rounds success is that it is the largest practical cartridge that can be easily adapted to small automatic pocket pistols. Is considered adequate for most self-defense situations and is the smallest caliber recommended for defensive ammunition.

.38 Special or Colt Special - .38 Special is designed for revolvers. Revolvers designed to fire .38 Special should never be used to fire .357 Magnum ammunition.

.38 Special

.38 Special is designed for revolvers. It is probably the most popular revolver cartridge ever produced, and is easily found in most parts of the world. The .38 Special comes in standard and +p variants. Not all .38 revolvers and some older revolvers are not designed to handle the more powerful +P ammunition, so check to verify your firearms ability to shoot it. Also known as the .38 Colt Special, this cartridge was developed by Smith & Wesson and was introduced in 1902. The .38 Special is considered one of the best-balanced, all-round handgun cartridges ever designed. It is one of the most accurate and widely used for match shooting.

9mm Parabellum or 9mm Luger or 9mm Para, or 9x19mm, or 9mm NATO

The 9mm Parabellum (et.al) is perhaps the least expensive of all self-defense rounds. It is more powerful than the .380 ACP, but like the .380 ACP it easily lends itself to firearm designs which are small and light enough to carry comfortably. 9mm is one of the most popular calibers for concealed carry.

This cartridge was introduced in 1902 along with the Luger semi-automatic pistol. The pistol and cartridge was first adopted by the German Navy in 1904 and then by the German Army in 1908. This cartridge has since been adopted by the military of practically every non-Communist power. It has become the most popular and widely-used handgun cartridge in the world. Performance wise, the 9mm cartridge has somewhat more power than the .38 Special but falls well short of the .357 Magnum.

.40 Smith & Wesson (S&W)

This cartridge was developed as a joint venture between Winchester and Smith & Wesson in 1989. It was an effort to to create a cartridge with the same power as the 10mm Norma round that the FBI had just started using, but in a shorter case. The shorter cartridge would facilitate accuracy and allow use of a smaller, more comfortable grip frame. The .40 S&W has become the cartridge of choice for many law enforcement agencies in the United States. Typical bullet weight for this cartridge ranges from 135 to 180 grains with an average muzzle energy that approaches 500 ft-lbs.

.357 Magnum - Revolvers designed to fire .357 Magnum can also shoot .38 Special ammunition

This cartridge was introduced in 1935 by Smith & Wesson for its heavy-frame revolver. Using a lengthened and strengthened version of the .38 Special case, the .357 Magnum was rapidly accepted by hunters and law enforcement. At the time of its introduction, it was claimed to easily pierce the body panels of automobiles and crack engine blocks. While it has less power than .44 Magnum, it compares favorably to the 10mm Norma and .45 ACP, but with better armor penetration. Today factories offer over fifty different loadings in this caliber. Bullet weights range from 110 to 200 grains with an average muzzle energy exceeding 500 ft-lbs.

.44 Remington Magnum

Though it is an excellent hunting round, .44 Magnum is really too powerful to use for self-defense: It is difficult to shoot rapidly, and there's a high possibility of the bullet going straight through the intended target to hit innocent passersby. This cartridge was developed by Smith & Wesson and Remington, and was introduced in 1955 for a new heavy-frame 44 Magnum revolver. Today Ruger, Colt, Smith & Wesson and others make revolvers for this cartridge. This is a high powered pistol cartridge designed primarily for hunting. The .44 Magnum offers much more power than .357 Magnum. The average bullet weight of this cartridge exceeds 200 grains, and the average muzzle energy easily approaches 1000 ft-lbs.

.45 Glock Automatic Pistol (GAP)

Developed in 2003 by Glock and Speer the 45 Glock Automatic Pistol (GAP). The cartridge was designed to be used in the medium frame sized GLOCK 37 semi-automatic pistol. Typical bullet weights now range from 185 to 230 grains.

.45 Automatic Colt Pistol (ACP)

You'll find the ACP used to designate many different cartridges which were originally designed to be fired through semi-automatic or automatic firearms

This cartridge was developed by John Browning in 1905 and adopted by the United States Ordnance Department, along with the Colt-Browning automatic pistol, in 1911. It has also been made the official military handgun chambering by several other governments, notably Argentina, Mexico and Norway. The 45 Automatic is the most powerful military handgun cartridge in use today. This is a heavy and powerful sub-sonic round with bullet weights from 185 to 260 grains.

Note: There is an old round designed for revolvers: the .45 Colt (sometimes incorrectly called the .45 Long Colt). It is not the same as the .45 ACP: The case is longer and has a higher volume, making it potentially a more powerful round.

Different Types of Ammunition

Self Defense Rounds

Self defense rounds must be quality rounds. These are typically more expensive, but when my life is on the line - lower quality, cheaper ammunition is not what I want between myself and an attacker. So, for the rounds that you keep in your concealed carry firearm or your home protection firearm every minute except for practice time should be the best. There are variations, which are described below. Manufacturers continue to innovate and improve the high performance self defense round.

Two simple guidelines:

American ammunition is justifiably the best, as a general rule: Buy American. Recommended American manufacturers are Federal, Cor-Bon, Hornady, Remington, Winchester or CCI ammunition. Of course there are many who have different favorites for a variety of reasons - but to keep it simple, these are recommended for self defense round manufacturers.
Never use hand-loaded or re-loaded ammunition for self-defense. Use factory-loaded cartridges only. For the same reasons mentioned above. Nothing but the best will do for your personal safety.

Fire at least 100 - 150 rounds through your semi-automatic firearm to ensure reliable feeding and make sure the self defense round you have selected shoots smoothly in YOUR firearm. This doesn't really apply to revolvers, but you should still fire the ammunition you intend to carry to assure yourself of its accuracy.

Hollowpoint bullets (handguns) usually expand and stop in the human body, and thus the attacker absorbs much more of the bullet's kinetic energy. Innocent bystanders are considered safer because hollowpoint bullets are less likely to exit the attacker's body and go on to injure anyone else.

Standard Ammunition- Standard ammunition is just that standard. Less expensive than self defense rounds and best used for practice.

Shotgun Ammunition

Shotgun ammunition is measured in gauge rather than in caliber and because shotguns are very versatile firearms, ammunition manufactured for them comes in a very wide variety of types and varying sizes and power. The gauge number is on the shotgun ammunition box. Your shotgun ammunition much match the gauge of your shotgun.

Gauge

The term "gauge" describes bore diameter, but unlike "caliber" used for handguns and rifles, the larger the number, the smaller the bore (The inside diameter of the barrel). So a higher gauge number means the internal diameter of the barrel is smaller, while a smaller gauge number means the internal diameter of the barrel is bigger, so a 12-gauge bore is bigger than a 20-gauge bore. Shotgun ammunition is measured in gauge as well, rather than in caliber for handguns and rifles.

Gauge was defined by the number of solid balls the same diameter as the inside of the barrel that could be made from a pound of lead. Thus, the 10-gauge shotgun is larger than the 12-gauge, which is larger than the 20-gauge. While there are many different sizes, or gauges, of shotguns, the two most often recommended for home defense are 12 gauge and 20 gauge shotgun.

Shell Length

The length of the shell is another very important number. Not all lengths will feed in all shotguns. The common lengths are 2-3/4 inches, 3 inches, and 3-1/2 inches. The longer the shell, the more shot pellets and powder it can contain. Shotguns which are designed to load a shorter shell should never be used to fire a larger shell, even if the larger shell physically fits within the gun.This can be extremely dangerous as the gun may not be able to handle the higher pressures a more powerful ammunition produces.

Shell Type

There are three basic types of shells:

High brass shells are shells that have a brass base which extends up the shell body by about three-quarters of an inch.
Low brass shells are characterized by a relatively narrow band of metal around the base of the shell. Low brass ammunition is generally less powerful than high brass.
Active shells are formed entirely of plastic, except for a miniature metal button which holds the primer in the center of the case head. Active shells are useful for hunters and others whose ammunition might get wet in the field, because they are nearly impervious to rust.

Dram Equivalent (power)

Dram Equivalent will tell you how powerful the ammunition is. Originally, drams were a black powder weight measure, but now modern shotgun ammunition uses smokeless powder. Shotgun ammunition manufacturers use dram equivalents to indicate how much power the load has. The higher the dram equivalent number, the more energy the ammunition has and the faster the shot will travel.

Shotgun ammunition falls into three general categories:

BIRDSHOT - Shotgun ammunition which uses very small pellets with individual projectiles of less than .24" in diameter are designed to be discharged in quantity from the shotgun. The size of the shot is given as a number or letter--with the larger number the smaller the shot size. It is so named because it is most often used for hunting birds. The finest size generally used is #9 which is approximately .08" in diameter and the largest common size is #2 which is approximately .15"

BUCKSHOT - A type of shotgun ammunition that uses medium-sized to large-sized pellets of .24" in diameter or greater, designed to be discharged in quantity from a shotgun. Generally the larger the pellets, the fewer of them in the casing.

SHOTGUN SLUG - An individual cylindrical projectile designed to be discharged from a shotgun. As a single projectile, slugs must be carefully aimed to be effective.

Buckshot is generally recommended for home defense. The larger the buckshot the greater the stopping power and the greater the chances of over-penetration and injury to innocents in other rooms or buildings. If you are in a densely populated home or neighborhood you can minimize the risk of over-penetration by using small game loads of #6 Birdshot or smaller, but this sacrifices a great deal of effectiveness. Versatility in available loadings is a great strength of shotguns, but you must choose your loads carefully for your environment.

If you have a typical defense shotgun firearm with an 18"-20" open-choked cylinder barrel, the pellets will spread out about 1" for every yard of range.

Recommended Defense Rounds

Recommended Defense Rounds for 20 Gauge Shotgun

3" shell Federal "Classic" #2 buckshot (F207-2-5PK) with 18 pellets,

Winchester "Double XX" Magnum #3 with 24 pellets (X203C3B).

If your firearm cannot accept 3" shells choose the Remington #3 with 20 pellets (SP20BK5PK-3).

Recommended Defense Rounds For 12 Gauge Shotgun

The #1 buckshot is recommended. A standard 2 ¾-inch 12 gauge #1 shotshell contains 16 pellets of #1 buck and will produce an effective wound trauma to the attacker. In addition, #1 buck is less likely to over-penetrate and exit an attacker's body.

A standard velocity 2 ¾-inch #1 buck shotshell (16 pellet payload) from Federal, Remington or Winchester is your best choice.

If you have a typical defense or "shotgun firearm with an 18"-20" open-choked "cylinder" barrel, the pellets will spread out about 1" for every yard of range.

Recommended Rounds For Handgun Rounds For Self Defense

.380

Federal 90 gr. Hydra-shok (P380HS1 H)
Cor-Bon 90 gr. JHP - the most powerful .380 hollowpoint

.38 Special

4" or Longer Barrel - Cor-Bon .38 Special+P 125 grain JHP.
Remington .38 Special +P 158 grain (LSWCHP)
2"-3" Snub Nose +P Revolvers - Steel Frame
Federal 129 grain +P Hydra-shok JHP (P38HS1)
Remington 125 grain +P Golden Saber HPJ (GS38SB)
2"-3" Snub Nose +P Revolvers - Aluminum-frame snub nose .38 NON +P is recommended
Winchester Silvertip 110 grain JHP (X38S9HP).
Federal Low Recoil Personal Defense 110 grain Hydra-Shok JHP load (PD38HS3 H)

9mm Parabellum (9mm Luger,9x19mm, 9mm NATO, or simply "9mm")

Newer +P Models Cor-Bon 9mm 115 grain +P Jacketed Hollowpoint
Standard Pressure Federal 115 grain JHP (9BP)

.357 Magnum

Greater recoil rounds Federal .357 Magnum 125 grain jacketed hollowpoint (357B)
Remington full-power 125 grain semi-jacketed hollowpoint (R357M1)
less recoil rounds Remington Medium Velocity 125 grain Semi-Jacketed Hollowpoint (R357M11)
Cor-Bon 110 grain JHP
.357 Magnum revolver will be able to use the less-expensive .38 Special as a practice round, while reserving the more powerful and more expensive.

.40 Smith & Wesson

Cor-Bon 135 or 150 grain jacketed hollowpoint
Winchester Silvertip 155 grain jacketed hollowpoint (X40SWSTHP)

.44 Magnum

Cor-Bon's 180 grain or Federal's 180 grain (44B) medium-velocity JHP

.45 ACP

Federal 230 grain Hydrashok JHP (P45HS1)

Cor-Bon 185 grain Sierra JHP

Another Note: Another important thing to remember about handgun ammunition is that ammunition designed to be fired in semi-automatics is generally different in shape from ammunition designed for revolvers.

There are some rounds which, based on caliber, seem as though they should be identical -- but they are actually different as they are designed for either revolvers or semi-atomatic pistols.

Disclaimer: The information provided on this website is for information purposes only and is provided solely as a guide to assist you in forming your own opinions. Although the information on the website has been obtained from sources believed to be reliable, it is provided on an "as is" basis without a warranty of any kind. None of the information is legal advice or the opinion of any professional or expert. This website is not a substitute for formal, qualified instruction in the handling, use or storage of firearms. You alone are completely responsible for your use of a firearm.

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