The 9mm round, being one of the most widely used caliber of ammunition in the world, comes in every variation imaginable. From anti varmint shotshell to hollow point, self defense rounds and everything in between. There is a 9mm round for every occasion.

What is a bullet?

An entire round (projectile & casing) is often incorrectly referred to as a bullet. A bullet is actually just the top part of a round that, when fired, is shot out of a gun’s barrel. Each bullet type has its own specific function and purpose. Below are some of the more common bullet types used for 9×19 ammunition and other rounds.

Full Metal Jacket (FMJ):

A bullet with a harder metal coating, called a jacket, usually copper, that covers the bullets softer core, usually lead. The harder jacket decreases bullet deformation and, because the jacket fully encapsulates the lead core, there is less lead fowling in barrels. Note: If not otherwise described, a FMJ is implied to be round nosed or spetzer. In either case these bullets offer the least deformation and expansion, which maximizes penetration. Because of the decreased deformation, a FMJ is ideal for hard barrier penetration, like car windows, body armor, etc. A FMJ can be had on bullets, but are typically described as such, ie jacketed hollow point.

Semi Jacketed (SJ):

Defensive. AKA soft tip, because the exposed lead tip is softer than the harder partial casing. SJ bullets are typically good for self defense. The exposed soft lead flattens and expands on impact, dumping its energy efficiently into a target. A SJ can be had on many different bullet types, but unless describe, ie semi jacketed hollow point, round nose is implied. In the case of a semi jacketed round nose, the expansion is typically not as great as a comparable hollow point, but the penetration is better. Another common use for a soft tipped bullet is for use in guns that use tube magazines, like most lever action rifles. In this case, the bullets are aligned nose to primer. A hard nosed spetzer could strike and set off the primer of the round in front causing a catastrophic chain reaction.

Round Nose / Ball Ammo:

All purpose. Named after its round top, It can be jacket, partially jacketed or not jacketed. The Shape offers excellent feed reliability and good penetration (including hard barrier penetration, like windows and armor) and aerodynamics, because of the lack of edges to get hung up, or create drag. The streamline shape also minimizes expansion and deformation, which increases penetration depth and could add to over penetration, especially with bullets of greater mass. If over penetration is a concern, an expanding bullet should be used.

Spitzer:

All purpose. Its main characteristic is its pointed top. It can be jacket, partially jacketed or not jacketed. The Shape offers excellent feed reliability, penetration (including hard barrier penetration, like windows and armor) and aerodynamics, because of the lack of edges to get hung up, or create drag. The streamline shape also minimizes expansion and deformation, which increases penetration depth, but could negatively add to over penetration, especially with bullets of greater mass. If over penetration is a concern, an expanding bullet should be used.

Hollow Point (HP):

Defense. A HP is bullet with a hollow, cup shaped point. The hollow is meant to expand on impact. When expanded, the bullet resembles a mushroom. The purpose is for the bullets sudden expansion to increase its diameter, causing a larger permanent cavity in its target. Also, the expansion acts like a parachute, causing drag which transfers its kinetic energy into its target quickly, causing maximum damage and preventing over penetration. Hollow point bullets with less mass may not have the momentum to penetrate deep enough to reach vitals. In this case a less expanding bullet should be used.

Jacketed Hollow Point (JHP):

Defensive. The JHP bullet has a cup shaped, hollow point with a full metal jacket. Like any hollow point, the JHP is designed to expand on impact, increasing the size of the wound channel and suddenly and efficiently dumping its energy into its target. The addition of the jacket decreases lead fowling in a barrel and lead vapor in the air and can be used to control the expansion and shape of the expanded bullet. This way, manufacturers can fine tune the performance of a bullet.

Semi Jacketed Hollow Point (SJHP):

Defensive. The SJHP bullet has a cup shaped, hollow point with a semi jacket and soft tip. Like any hollow point, the SJHP is designed to expand on impact, increasing the size of the wound channel and suddenly and efficiently dumping its energy into its target.The SJHP combines the expansion of a soft tipped, semi jacketed bullet with that of a hollow point. A SJHP provides excellent expansion, especially in low velocity rounds where there might not be enough speed to cause a fully jacketed hollow point to expand properly. However, the expansion might not be as controlled or as severe as that of a JHP.

Wadcutter (WC):

All purpose. Exclusive to revolvers, with very few exceptions, due to semi auto feeding problems. The WC was initially designed for target shooting. Typically lead and unjacketed, its flat top and 90° shoulder punches a clean and visible hole in paper targets. As they are meant for target shooting, where velocity isn’t necessary, wadcutter rounds are often made to lower pressures. That being said, some feel the shape and soft lead efficiently dump energy into a target, the low velocity cuts down on recoil and the shape inherently offers more mass than a hollow point or round nosed bullet. So, wadcutters are often sought after self defense rounds.

Semi wadcutter (SWC):

All purpose. This variation of wadcutter has beveled shoulders and a more pointed, but still flat nose. It offers most of the features of a wadcutter, but with better aerodynamics and penetration. Mostly, the design’s beveled shoulders are meant to allow the SWC to cycle in semi auto pistols.

Shotshell:

Anti snake and varmint. Essentially, shotshells are shotgun shells meant for non-shotgun caliber guns. They are metal shells with a plastic cap that holds, small shot. They are not particularly powerful, but are good for small pests at very close range.

Frangible:

Multipurpose. Frangible bullets are designed to break apart into tiny pieces on impact. The tiny pieces have virtually no mass and will not over penetrate, minimizing the chance of collateral damage. The bullet will also disintegrate if it hits a hard surface, which eliminates the chance of dangerous ricochet. They are ideal if a defensive shooting were to take place in a crowd or if shooting against a hard backstop.