When it comes to purchasing a handgun for personal protection, one of the key decisions you will face is choosing the right caliber. This guide provides an overview of the most common handgun calibers and the differences between Full Metal Jacket (FMJ) and Hollow Point (HP) bullets.
What is Caliber?
A way of thinking about caliber that helped me understand it is to compare it to needle gauges. Needle gauge size is a measure of the thickness of the needle. All needles generally do the same thing but you might use a different size needle depending on the job or application.
Instead of gauge, we use the word caliber to describe the size of the firearm’s bore diameter which also applies to the diameter of a bullet. The diameter can be measured in both inches and millimeters (mm).
Ammunition Components
Before we dive deeper, let’s clarify some terminology.
There are four main parts to ammunition: casing, bullet, propellant, and primer. The bullet refers to the projectile itself. The casing, which encloses the components, can be made of brass, aluminum, steel, or even polymer. Housed inside the casing is the propellant (gun powder), primer, and bullet. The entire assembly is known as a “cartridge.”
Bullets come in various weights, also referred to as “grains”. For instance, a popular 9mm bullet weight is 124 grains. To give you something to compare that to 7,000 grains makes up a pound.
Additionally, factors such as the amount/type of propellant and bullet weight determine the velocity, expressed in feet per second. This velocity, along with other factors, can influence the round’s physical stopping power.
Stopping Power
Don’t let internet armchair experts fool you; there really isn’t a difference in stopping power between calibers. Greg Ellifritz at Active Response Training analyzed over 1,800 real-world shootings and found that there really is no discernible difference between calibers as it relates to stopping power.
Greg’s research revealed that in a significant number of shooting incidents, the aggressor stopped their violent actions after being struck by a single round, irrespective of the caliber or shot placement. This phenomenon, known as a “psychological stop,” suggests that the mere threat of injury from a gunshot can deter further aggression. This is commonly referred to as the FIBS (Fu** I’ve Been Shot) factor.
While larger caliber rounds demonstrated greater physical stopping power in Greg’s study, smaller calibers were equally effective in incapacitating aggressors when coupled with precise shot placement. This highlights the importance of accuracy over caliber size in achieving desired outcomes during defensive encounters.
Ultimately, Greg’s research underscores the importance of being able to quickly get multiple shots in the right placement. Regardless of caliber, achieving accurate hits on vital areas such as the head or torso is crucial for immediate incapacitation of the threat.
As the evidence shows, caliber doesn’t really matter that much so consider these two things when choosing the right firearm for you:
- select a gun that you’ll actually carry
- select the largest caliber that you’re comfortable shooting (and comfortable paying for)
Common Handgun Calibers
.22LR – This is a rimfire cartridge that is popular for recreational shooting and small-game hunting. It is the smallest and lightest caliber, making it a great choice for beginners to develop their shooting skills. It can be used for defensive purposes but may not be as effective in physically stopping an attacker. On the plus side, this is usually the least expensive ammo coming in at around $0.05 per round.
.380 ACP – This is a popular caliber for concealed carry due to its compact size and relatively low recoil. Just like with the .22LR, it may not physically stop an attacker as well as a larger caliber. It’s not as widely manufactured and it usually costs around $0.35 per round.
9mm Luger – This is probably the most common choice for self-defense due to availability and moderate recoil that is easy to manage. Because its so prevalent, you can usually find it for around $0.25 per round.
.40 S&W – This caliber was favored by law enforcement for its stopping power but has more recoil than 9mm. It also costs around $0.40 per round.
.45 ACP – This is a classic caliber that is widely used for military applications. It is known for its power but also has a very pronounced recoil. It can usually be purchased for $0.50 per round.
10mm – The “big brother” of .40 S&W with significant felt recoil which may not allow for quick follow up shots. Not as common as the other calibers which is reflected in it’s price at around $0.65 per round.
Differences Between Full Metal Jacket and Hollow Point Bullets
Full Metal Jacket (FMJ) bullets are typically made of lead or a lead-alloy encased in a copper jacket. FMJ rounds are designed to penetrate the target without expanding upon impact and will typically pass through whatever they hit. Because of this, it’s crucial to hit vital areas to ensure the stopping of an attacker. The main drawback of FMJ bullets is the risk of passing through the target and potentially harming bystanders. They are generally cheaper than Hollow Point (HP) bullets, making them suitable for practice or range use.
Jacketed Hollow Point (JHP) bullets, on the other hand, are engineered to expand upon impact, causing more damage and reducing the risk of over-penetration. These bullets are designed to slow down and transfer their energy upon hitting the target. As the bullet’s nose opens or “mushrooms” upon impact, it releases its energy rapidly, ideally stopping inside what they hit. While HP bullets are typically more expensive than FMJ bullets, they offer a higher level of effectiveness in defensive situations.
Conclusion
Generally, a Jacketed Hollow Point (JHP) bullet in 9mm or above offers optimal effectiveness in defensive scenarios. However, your comfort and proficiency with your chosen firearm are paramount. Therefore, investing in comprehensive firearm training to hone marksmanship skills is key for individuals seeking to enhance their ability to defend themselves effectively. I explore this topic, and more, in my classes. You can find my class schedule here or at https://ftsfirearmtraining.com/training/