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  • Post last modified:August 18, 2023

Have you heard about the comparison between TMJ VS FMJ?

TMJ stands for Total Metal Jacket, and FMJ stands for Full Metal Jacket. Are there any significant difference for gun owners to know? 

Of course! Here is why.

What Is Total Metal Jacket Bullet

tmj vs fmj

TMJ bullets possess a soft lead core and feature a complete covering of a thin copper layer, called a copper jacket. They also have an enclosed base, which prevents any lead exposure on the bullet itself.

Imagine total metal jacket (TMJ) bullets as a superhero wearing a full-body copper suit of armor, designed to protect people at indoor shooting ranges or those who shoot a lot from the villainous lead exposure.

This copper armor is carefully applied using a process called electroplating, creating an enclosed base that ensures no lead can escape.

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These TMJ rounds mainly come in handgun calibers, with Speer Lawman and Blazer by CCI acting as the famous costume designers for this type of ammunition.

Just like their full metal jacket (FMJ) cousins, TMJ ammo is perfect for target practice and casual shooting adventures, as it's more affordable than the more specialized jacketed hollow point (JHP) ammo.

What Is Full Metal Jacket

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FMJ ammo is Ideal for target practice and casual shooting, FMJ ammo is popular among shooters of all ages, including 15-year-olds. It's easy to find, most calibers offer FMJ products, and they are affordable to train at high volume.

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The military also exclusively uses FMJ ammo following The Hague Convention of 1899, which bans expanding bullets in warfare.

Picture a soft marshmallow (the lead core of a bullet) wrapped in a hard candy shell like an M&M. This shell, made of materials like copper alloys, gives the bullet more support and prevents deformation during firing.

Invented by Col. Eduard Rubin in 1882, the full metal jacket (FMJ) allowed bullets to fly faster without leaving lead residue in the barrel, transforming bullet technology. However, the process leaves a tiny bit of exposed lead at the base, like a small marshmallow peeking out.

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Is TMJ ammo good for self-defense?

Imagine TMJ rounds as a special type of water gun that's perfect for target practice but not good for self-defense. These water guns shoot plain, round-nose water balloons that can only pop on paper targets, and they aren't designed to change shape or cause extra damage.

Using TMJ bullets in a self-defense situation would be like shooting a water balloon that goes right through the bad guy and accidentally hits someone else.

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For self-defense, you need a better water gun loaded with Jacketed Hollow Point (JHP) balloons. These water balloons are designed to expand when they hit something, making a bigger splash and slowing down so they don't accidentally hit anyone behind the target.

If you're looking for some well-known TMJ water guns you can find at local stores in the United States, check out Speer Gold Dot, Federal HST, and Hornady Critical Defense. Just remember to save the TMJ rounds for target practice and use JHP ammo for self-defense.

Why not use FMJ for self-defense?

Using FMJ ammunition is like playing with a toy car that's cheaper and doesn't need to be cleaned as often. However, because these toy cars don't have special brakes or an expanding bumper that helps them stop, they tend to zoom right through whatever they hit, like a soft pillow or a playtime barricade.

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The lack of an expanding bumper means that the toy car doesn't slow down as much or create a larger impact, making it less effective at stopping the "bad guys."

Imagine you're playing with your toy car and you need to protect your toy city. You want a car that can stop the bad guys without accidentally zooming through and hitting something else.


When you're using FMJ bullets, always be aware of what's behind your target, like innocent toy citizens or buildings, so you can keep them safe.

A better choice for self-defense would be a toy car with an expanding bumper, which can create a bigger impact and slow down more effectively, increasing its stopping power.

Which Bullet Type Is Better For Training

FMJ is the best for training hands down. Whatever caliber you shoot, FMJ remains the lowest cost to train at high volume.

Which Is For Personal Defense

For personal defense, JHP, Jacketed Hollow Points are the preferred choice. Learn more about FMJ vs JHP here