About Ammunition

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Pistol Ammunition

Pistol ammunition is designed to fit the size of your gun based on caliber, gunpowder (smokeless powder), and firing mechanism. Ammunition, or bullets, are technically called cartridges. Cartridges (for pistols) come in two basic styles: Rimfire and Center fire. The primary difference between the two is the location of the firing primer, which is a chemical mixture designed to create a spark which ignites the gunpowder (smokeless powder) which in turn, propels the bullet down the barrel.
In the Rimfire design, the primer compound is located in the fold of the rim or base of the cartridge. In a Center fire design, the primer is located in a special casing (cup) located in the center base of the cartridge. Rimfire pistol designs utilize a firing mechanism designed to strike the rim of the bullet and are commonly not recommended for dry fire practice as firing a Rimfire pistol with an empty chamber can damage the firing mechanism. Center fire pistols have a firing pin which is aligned to the center of the primer cup in the cartridge. Because of their differences, a Center fire pistol can be dry fired with no damage to the firing mechanism. As always, check your owner's manual for additional details.

Cartridge Components

There are four primary components to any cartridge design:

Cartridge Case

Constructed commonly of brass, though steel and nickel-plated cartridges are available, the case consists of the body portion of the ammunition, where the top end is known as the neck and mouth and the bottom end is known as head.
Technically, the Rimfire bullet does not have a primer, rather, it has a priming compound located in the fold of the case rim located at the head of the bullet. Center fire ammunition contains a primer "cup" which holds the primer, with a flash hole in the cartridge which sends the primers "spark" through the bottom, or "web" portion of the cartridge to ignite the "smokeless powder" inside the cartridge case. Stamped on the head of the primer is the information about the cartridge, such as its caliber size and manufacture.
There are several types of cartridges available, each with a specific design and purpose. Case bodies can be straight, which are the most common for self-defense ammunition as pictured to the left. The other type of body style is referred to as the bottleneck style, where the neck is considerably smaller than the body, similar to the first set of cartridges displayed. This type of ammunition is commonly used in higher-end rifle models.
Case heads come in five basic configurations: Rimmed, Semi-Rimmed, Rimless, Rebated-Rimless, and Belted-Rimless, all of which are designed for the gun in which they are intended for use.

The primary design of the cartridge is to ensure it holds the components in their proper position, aligns the bullet to the bore for proper rifling when fired, and to expand slightly against the barrel, which creates a tight seal to prevent gasses from escaping towards the rear of the barrel. Once the bulled has been expelled, the cartridge, as it cools down, retracts away from the barrel making it easy to extract.


The primary job of the primer is to create a spark which ignites the black powder (smokeless powder) inside the cartridge. The primer is shaped similar to a cup, and inside it is a layer of priming compound covered by an anvil. When the firing pin hits the center of the primer cup, it pushes against the anvil which compresses the priming compound and causes a spark to occur. The spark then escapes through a small hole into the main cartridge case where the gunpowder reacts by exploding.

Gunpowder (Smokeless Powder)

Although we have been using the term "gunpowder" to describe the chemical contained within the cartridge, today's modern firearms use a chemical known as "smokeless gunpowder. Referring it to "gunpowder"  is a layman's term for smokeless-gunpowder which is the technical term for today's modern ammunition. Smokeless gunpowder, consists of nitroglycerin or a combination of nitrocellulose and nitroglycein (known as double-base powders). Similar to gunpowder, when the primer produces it's spark, the powder is ignited and creates an explosion of gasses which propel the bullet down the barrel at a high velocity.


Pistol bullets, like cartridges, are available in a wide range of options and can be constructed of different materials. All bullets contain lead, so it's important you take the proper precautions when handling ammunition. The bullet can be cast or swaged to the proper dimension and shape or it can be surrounded by a thin layer of copper, known as a copper jacketed bullet. Copper jacketed bullets can travel at higher velocities and designed to give optimum terminal performance for its intended purpose. The performance of the bullet while traveling towards its target or on impact depends on its construction, shape, what it is designed to accomplish on impact.


The caliber of a bullet refers to its size in diameter. Most pistols are designed to fire a specific caliber with a specific rating on the amount of grams of smokeless powder contained within the cartridge. Some pistols can accept two different calibers, such as the .357 Magnum handgun which can also accept the .38 Special handgun ammunition.  Another well-known caliber is the .44 Magnum handgun which can also shoot the .44 Special ammunition. While these combinations are possible, we suggest consulting your owner's manual before attempting to shoot a bullet your gun is not specifically rated.

Naming Convention

There is not a universal naming convention for ammunition being sold in today's market.

In essence, the first part of the name of a cartridge refers to the diameter in millimeters or in decimal inch measurements (known as the caliber). In the U.S., most of our ammunition is listed in caliber measurements whereas in other countries overseas, cartridges can be labeled by diameter and length, such as 9 X 19 mm.

The second half of the designation can be named after the company that created it, an individual who designed it, or it can include a special designated name, such as "special" or after some military design, such as "webley". Other cartridges have both the decimal and the metric designations listed, such as the .32 ACP and 7.65 mm Auto. And, as if naming the cartridge using different standards isn't enough, some ammunition will be known by more than one name, such as: 9 mm Para, 9 mm Parabellum, 9 mm Luger, and the 9X19mm.

Using the correct Ammunition

Using the correct ammunition and caliber size is extremely important for safe gun operations.
Label on Ammo Box
Identification on Cartridge Case Head
.38 Special Designation on Barrel
.38 Special with +P Desination on Barrel
.45 on Ejection Port Semi-Automatic Pistol
.45 on Slide of Semi-Automatic Pistol
There are several ways to determine which size ammunition you have and which size fits the firearm you own. To identify boxed ammunition, simply locate the label for important information, such as the caliber, cartridge name, and weight in grains. On the bottom (or the head) of the bullet itself, check to see which caliber has been stamped. For revolvers, you can check the barrel for the designated cartridge size whereas on the semi-automatic, the caliber can be located on the ejector port or on the slide. As always, you can check the owner's manual for additional ammunition options or take your firearm to a local gunsmith for proper identification.

Ammunition Safety

Incorrect Caliber or Capacity Rating

Ammunition, in-and-of-itself is a fairly safe to handle and to store. The most important consideration is to ensure the information on the ammunition box, the head of the cartridge, and on the barrel of the gun agree with one another. It's possible, for example, to load a 9mm magazine with a .380 bullet (since it is smaller) by mistake, which could result in serious damage to yourself or your firearm. Always verify the information before loading the firearm.

Aside from caliber, pay attention to any special designations on the ammunition box, barrel, or cartridge. Some ammunition can be the same caliber as the gun but have a special designation such as +P and +P+ which means the cartridge is designed for a gun that was especially built to withstand a higher capacity bullet. For example, the frame and barrel for these higher capacity bullets is likely to be reinforced or perhaps a bit thicker than the standard caliber. While you can shoot the standard caliber load in a gun with a +P or +P+ designation, you cannot use +P or +P+ in a gun which was built for standard capacity bullets without running a risk of serious damage to yourself or your firearm. A typical example would be the .38 Special handgun where the ammunition is also available in extra capacity loads of .38 Super Auto and the +P; using these extra capacity loads in a standard .38 Special handgun could cause serious damage--always be sure you are using the correct ammunition designated for the gun.

Ammunition in Fires

It's a proven myth that ammunition which is engulfed by a fire will start discharging bullets in a multitude of directions. Ammunition, especially the bullet itself, relies on the compressed, enclosed, limited space of the handgun barrel to compel and discharge the bullet at a high velocity rate in the direction the gun is pointed. In a box, ammunition lacks the compressed, enclosed, limitation of the barrel and therefore simply bursts apart, much like a dropped glass, in many different directions at a relatively low rate of speed. Unless you are extremely close to the ammunition or some of the fragments manage to travel to a sensitive are of your body, like your eyes, the chance of actual injury is extremely small.

Ammunition in Safes

Ammunition, like a firearm, should be locked in a safe, away from unauthorized users. Ammunition is pretty viable and long lasting although there are many instructors who suggest replacing ammunition every 6 months. Ammunitions largest enemy is humidity and exposure to water, solvents, lubricants, and other common household chemicals. Storing ammunition in a safe allows you to secure the ammunition, keeping it in a safe and enclosed location, and away from contamination.

Disposal of Ammunition

Ammunition that has been in a flood or fire, exposed to solvents, oils, or other liquids should be disposed of in a safe and responsible manner. Refer to the Sporting Arms and Ammunition Manufacturer's Institute (SAAMI) web site for additional information.

Cartridge Malfunctions

As with anything mechanical, no matter how well it's built, no matter how careful you are, there's always the chance a malfunction will occur. There are three types of cartridge malfunctions:


: A misfire occurs when the primer does not sufficiently spark, preventing the smokeless powder from igniting and discharging the bullet.


: A hangfire is a delay in the primer igniting after the firing pin has struck the cartridge. This can be typically mistaken for as a misfire. It is very important to keep the pistol pointed downrange for 30 seconds, allowing sufficient time for the primer to ignite and discharge the bullet. While it is very tempting to want to check on the the pistol action, it is not advised to do so until the 30 seconds have passed.

Squib Load

: A squib load is a reduction in pressure when the primer is struck and the smokeless powder ignites. Squib loads are very noticeable as the loud sound associated with the discharge is lower than usual, the muzzle flash is not the same, and/or the recoil is less. When this occurs, wait at least 30 seconds keeping the pistol pointed downrange. When the time is up, empty the magazine, clear the chamber, and check the barrel for obstructions. If a bullet is lodged in the barrel, do not continue to use the gun--take the gun to an authorized gunsmith for a complete safety inspection before using it again.

Self-Defense Calibers

There is a wide variety of calibers available in today's marketplace. Our discussion is centered on the most commonly used calibers for self-defense, therefore we will be limiting and dedicating this section of our education program solely to the common, primary self-defense calibers.
Note: While .22, .25 ACP and .32 calibers are commonly sold as personal defense calibers, they are generally not considered powerful enough to use in a self-defense situation, especially when the attacker is particularly large or under the influence  of drugs or alcohol.

However, any gun is better than none! These calibers will stop and kill a person if they hit vital organs or if enough of them are used to slow down the attacker--they will have an impact! If you are older, weaker, or for some other reason you cannot control a larger caliber weapon, by all means include these lower caliber bullets as part of your self-defense strategy.

.380 Automatic

The .380 Automatic is generally the lowest, acceptable caliber to use for personal self-defense. It is considerably larger and more powerful than the .22 LR and possess a relatively low recoil response, making it ideal for older adults, adults who are weak, and adults who have a physical disability which limits them for using higher-capacity weapons. The cartridge is small enough to adapt to smaller, personal style firearms, such as those that can be carried in the pocket or a fanny pack without drawing attention.

.38 Special

The .38 Special caliber is arguably one of the most popular revolver calibers ever created. This caliber cartridge is also known as the .38 Colt Special and comes in both a standard and a +P load. Since it is available in multiple grains, the pistol owner should be careful during their purchase of ammunition, ensuring to get the correct load for their pistol. The .38 Special is a well-balanced bullet and used in competitive matches throughout the U.S. as a standard.

9mm Parabellum, Luger, Para, NATO, and 9X19mm

The 9mm Luger (et. al) is arguably the most popular caliber for the semi-automatic personal carry firearm. More powerful than the .380 ACP, yet slightly larger, the 9mm Luger can be adopted for smaller concealed carry personal pistols. Used widely by law enforcement agencies, private security companies, and thousands of citizens, the 9mm pistol is an extremely popular sized bullet. Many "compact" pistols (such as the Springfield-Armory XDm model), can be carried on your person without detection provided the appropriate concealed carry method is used. 9mm semi-automatic pistols can come in both single and double-stack capacity magazines, which can carry up to 13 or more rounds in a single magazine. The 9mm caliber has a moderate recoil "kick" which requires the shooter to realign their target after every discharge, but it does not require an excessive amount of time to do so. In a self-defense situation, the decision to use a firearm occurs within a distance of 20 +/- feet, meaning, aiming the pistol accurately each discharge is rarely a consideration--firing the pistol in the general direction of the attacker is usually all that is required to acquire the target.

.40 Smith & Wesson

The .40 Smith & Wesson caliber bullet is constantly under development. It is a size that Winchester and Smith & Wesson believe can be a compromise between the smaller 9mm and the larger .45 caliber bullet.

The .40 caliber bullet is constantly receiving multiple performance reviews--some say its "great" as newer versions feature it as a lighter bullet with more power; others say it falls short of its larger, heavier .45 caliber cousin in terms of stopping power. The .40 Smith & Wesson is the lowest caliber considered to be efficient against wildlife, such a small lion or bear. This is a situation where personal concealed carry is being intermingled with practical, self-defense weapons against aggressive wildlife.

Choosing a caliber should be based on the situation, not the caliber.

In other words, if you are planning to go into the woods, a pistol capable of stopping a Black Bear encounter is completely different from a pistol capable of a personal defense against a fellow human being. If you are in the city and carry a weapon designed to stop an American Black Bear and use it in self-defense, you can bet there will be questions raised by the police during an investigation process.

The purpose of a personal defense weapon is to eliminate the immediate threat of personal loss to limb or life. The .40 caliber cartridge in "pushing the edge" against the personal defense level of self-protection.

.357 Magnum

The .357 Magnum cartridge can shoot the .38 Special cartridge bullet. The .357 Magnum cartridge could be considered "over-kill" in terms of caliber choice for personal defense. There's no reason to carry a .357 firearm or larger solely for personal defense. The .357 caliber is designed for one thing, and one thing only, to destroy anything within its path!

If you are protecting yourself with a firearm for the purpose of self-defense, you could be over-stepping boundaries using such a high caliber weapon. There's a difference between "reasonable" and "excessive" force; we encourage you to speak with an attorney before you consider a .357 or higher caliber for the purpose of self-defense.
Note: Any caliber over a .40 could be considered "excessive" for the purpose of self-defense. When it comes to personal protection using a firearm, you should discuss caliber options with an attorney. Although it's never been presented in a court of law (that we can find), a prosecutor for the State could argue any size over .40 caliber could be excessive for personal defense. ALWAYS talk to an attorney regarding personal protection methods, acceptable means, and excessive force--especially when it comes to a personal firearm.

.45 Glock Automatic Pistol (GAP)

This is a fairly new caliber which was introduced in 2003 for the purpose of having a caliber that would fit Glock's medium size frame pistols.

.45 Automatic Colt Pistol (ACP)

This cartridge is used by today's military because of its power and effectiveness in combat situations. Designed originally for the Colt-Browning 1911 semi-automatic pistol, it is arguably one of the largest rounds available and incorporated into personal defense carry scenarios.

Round verses Hollow Point Bullets

There are four basic bullet types: Full Metal Jacket (FMJ, (aka Round (solid lead), Jacketed Soft-point (JSP) Bullet (designed to expand after deep penetration), Jacketed Hollow Points (JHP), designed to expand on or quickly after penetration, and Plastic-tipped Bullets (PTB), designed to penetrate first, then expand. As with all ammunition, there are several variants available for the firearm owner to choose. Both caliber and bullet characteristics must be carefully weighed when considering the correct ammunition for personal protection. Be sure to consult an attorney beforehand to ensure the caliber and bullet characteristics are legal in your state, under which condition(s), together with when and how you can transport the ammunition.

Full Metal Jacket (FMJ) Bullets

Full Metal Jacket bullets, as described earlier, are made of lead and generally have a layer of copper covering the lead. The copper can cover the total bullet (total metal jacket) or simply cover the exposed and rear-side of the lead component of the bullet. Copper is added to increase the strength of the bullet (as a projectile), maintain its shape while traveling through the barrel and towards the target, and finally to be a thin enough layer as to no impede the performance of the bullet on impact.

Full Metal Jacket bullets are designed for penetration which makes them ideal for range use when you know there is nothing that is beyond the target. FMJ bullets tend to pierce their targets, making the entry and exit holes relatively small in diameter and are the only style bullet which can be used in a combat situation, such as a war.

Jacketed Soft-point Bullets (JSP)

Jacketed soft-point bullets are designed to expand after penetration in the target has occurred.  They are typically identified as having a flat tip verses the pointed, round, or hollow point characteristic found in other bullets. JSP bullets penetrate deeper and rapidly decelerate once the subject or target has been hit, producing a deeper level of penetration and resulting damage than the Full Metal Jacket and the Hollow Point bullet. These bullets are designed to meet in the middle between the full metal jacket and the hollow point bullets in terms of impact reaction, however, it's important to note most modern semi-automatic pistols are designed for hollow points, not soft-point bullets.

Jacketed Hollow-point Bullets

The hollow-point bullet is explicitly designed to expand on impact in order to reduce the chances of exiting the target and hitting an unintended target behind the initial target. The bullet loses penetration power immediately upon impact, expands, and causes significantly more damage to the target as it slows down. Hollow-point ammunition is considered the "premier" choice for personal protection purposes because it can stop an attacker without exiting and causing collateral damage to innocent bystanders. On the other hand, since these bullets are designed to increase the impact diameter, they can cause additional internal damage and can cause a larger exit wound; they may be banned from use within your state. As always, check with a qualified attorney in your state to see if hollow-point bullets can be used, under which conditions, and how to safely transport them from place to place.

Plastic-tipped Bullets

Plastic-tipped bullets are essentially hollow-point bullets filled with a hard plastic which prevents expansion on impact, but allows expansion quickly thereafter. The concept and its application is based on the theory the hollow-point bullet expands too quickly if the target has thick clothing or some other form of protective clothing. Whereas, the fully-jacketed bullet may penetrate the thick clothing, but not provide sufficient damage to the target. Plastic-tipped bullets (according to our research) have never "taken-off" in terms of a self-defense bullet. In its defense, it's a relatively new design and perhaps it has not had sufficient time to gain in popularity.
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