Ammo Basics: Jacketed and Hollowpoint

Another difference in ammunition is whether the bullet in the cartridge is a jacketed or hollowpoint variety. All ammunition can be sub-divided among one of these two categories. Although both are very popular, each kind has its own specific specialty.

Both hollow point and full metal jacket ammunition is sold all the time at all hunting and firearm stores. Both kinds feed reliably through the firearm they are designed for, and both generally have a similar "kick" in the firearm when discharged. So what is the big difference between the two?



Full Metal Jacket bullets mean the bullet on top of the cartridge is completely covered in a metal case. Basically a solid piece of metal, the Full Metal Jacket bullet is not meant to expand in any way when it strikes a target.


The following photo is a closeup of a .40 caliber round of ammunition with a full metal jacket bullet and a .38 special caliber round of ammunition with a full metal jacket bullet.


Although they look different from one another and come on different sized cartridges, both are designated as full metal jacket bullets.

When a full metal jacket bullet strikes a target, by its design, it attempts to pass straight through the target and continue on. For thick or large targets, or for targets located behind an obstruction, Full Metal Jacket ammunition would be the kind of bullet you want to use. But Full Metal Jacket ammunition, although fantastic for penetration of targets, does not do the same kind of damage to a target as hollow point bullets do.


A hollow point bullet has a open tip at the end. Some varieties have a small cavity, other types have a deep indentation, and other kinds have additional components inside the opening. The purpose of all these is to cause the bullet to expand when it reaches the target.


A hollow point, when it reaches a soft target, will flatten out and expand. This is due to fluid entering the hollow point tip and pressing the walls of the bullet outward. This fluid entry also causes the bullet to spin and tumble as it moves through the target. Usually the bullet takes a mushroom shape when it expands, and causes considerably more damage as it moves through the target in its wider form. The initial expansion of the bullet also transfers the overall energy of the discharged bullet throughout the target.

Hollow points do not have as large a risk of ricocheting as full metal jacket ammunition, but do not tend to penetrate as much as full metal jacket ammunition does. These are both due to the design of the bullet. Since they expand immediately on fluid impact, they are less likely to proceed completely through their intended target.


There are sub-varieties of hollow point and full metal jacket ammunition, but I will review them in later blog entries. There are also many passionate discussions on the merits of hollow point versus full metal jacket ammunition on their respective effectiveness on stopping assorted targets. That is also for another blog entry.

No matter the type of bullet, there is absolutely no substitute for practice. Practice hitting your target, and make your hits consistent in critical areas at the target range. No fancy ammunition will ever be able to do that for you.

A bit of trivia: The Hague Convention has banned hollow point bullets (expanding or fragmenting) in all warfare situations and all declared wars... ideally to stop the suffering of soldiers in combat. But hollow point bullets are the favorite of police and private citizens worldwide for the massive damage they can cause to a target and also for their reduced risk of over-penetration.

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