How Much Do You Really Know About Gun Calibers?

If you’re just getting started with target practice or want to provide some personal security for your home, the world of gun culture can make you feel like you’re back in the Wild West — and completely out of your depth.

From calibers to gauges, what do you really need to know in order to assure you’re getting the right caliber ammunition for your weapon?

Before you ask, yes, there is a difference between calibers and gauges even though they technically measure the same thing: what size ammo will work with a certain type of firearm. To be more specific, caliber refers to the diameter of bullets for either a rifle or a handgun, while gauge is the measure of the inside diameter of a shotgun barrel.

This guide will walk you through the most common topics you’ll need to gain familiarity with this new world.

Guns or Ammo?

There is a fair bit of confusion about whether the numbers you often see associated with a gun are describing the ammunition or the weapon itself. The answer is both: a .38 Special uses 38-caliber bullets, but a .30-30 gun uses bullets that are .308 inches in length. Why the difference in naming conventions?

Over the years, some gun manufacturers have developed their own terminology while other gun and ammo naming has come from the bearers. There are no true set standards for calibers, but there are some general guidelines that most types of ammunition follow.

The Most Common Calibers

While there are perhaps double this number, there are fewer than 15 calibers that you’ll encounter in standard situations. Target practice and personal protection are the two key needs for most gun beginners, and the calibers most appropriate for those uses are listed below in terms of ultra-lightweight to heavyweight stop-a-tank rounds:

• .22 LR – In terms of units sold, this long-rifle .22 is a mild entry into the rifles category, with negligible recoil and a relatively quiet shot.

• .25 ACP – ACP stands for “Automatic Colt Pistol” although there are plenty of other handguns that utilize this round. It is a lightweight in terms of stopping power.

• .380 ACP / 9mm Short – Here’s where the confusion starts. These two names refer to the same handgun round, which is found in many pocket pistols used for personal protection.

• 9mm / 9mm Luger – Also a handgun round, this particular caliber is powerful enough for personal protection, with a low price-point and low recoil. The 9mm ammunition is the size used by police forces around the world.

• .45 ACP – A larger bullet that powers a handgun with moderate recoil. Most often used by law enforcement, it boasts plenty of stopping power.

• .38 Special – Standard-issue for FBI agents for many years, you’ll see more of a recoil in this handgun as there is more powder in the cartridge — which is longer than the .45 ACP.

• 12 Gauge – 12 gauge and 20 gauge are the most popular sizes for target practice with shotguns. The variations available within these sizes are significant, from buckshot to birdshot and slugs available.

Check out the video below to learn more!

~ Firearm Daily