Ammo 101: A Beginner’s Guide to Ammunition

For someone new to firearm ownership, it may be surprising to discover that there can be as much complexity regarding different types of ammunition as there is in selecting the firearm itself. Here’s a quick guide to understanding different characteristics of ammunition so you can determine which ammo might suit your needs.

Ammo is primarily classified by its caliber, or the actual physical dimension of the round, either in inches or in millimeters. “.40 Cal”, pronounced “forty caliber”, refers to a bullet with a diameter of 0.4 inches; likewise, 9x19 mm describes a bullet that is 9 mm in diameter and 19 mm long. Your firearm is likely chambered in only one caliber, and should only be fed ammo of that same caliber.

An ammo’s load describes how much gunpowder is used to propel the bullet. A round’s load and grain will together define what the bullet is capable of doing once fired. The weight of the bullet is usually measured in grains, sometimes in grams. The higher the grain of the ammo, the heavier it is, meaning that unless it has a high load, the heavier bullet will travel slower than a lighter bullet. If the bullet has a high grain, and also moves very fast due to a powerful load, then it will transfer a lot more energy onto the target, making it a more powerful round. Ammo types that have a lighter grain, but powerful load, such as 55 grain 5.56 mm ammunition, will travel very quickly, making longer range shots easier to land.

The type of ammo determines what happens when the bullet hits your target. Hollow point rounds are great for self defense, since they do maximal damage to an aggressor while minimizing unwanted barrier penetration. Full-metal jacket, or FMJ, rounds are usually cheaper, so although they have sub-par performance against threats, and will over-penetrate soft barriers, they are great for practice at the range.

For more information, please contact Dennis Leifheit at:

Northern Illinois Carry, LLC

405 Somonauk St.

Sycamore, IL 60178

(815) 501-9421

www.northernillinoiscarry.com