How do bullet calibers work

A 9mm bullet is the same diameter as the bullet used in. Each of these cartridges fires a projectile approximately. The difference between each round lies in the powder charges and cartridge length, not the size of the projectile they fire.

From left to right:. All use. So what do all those extra numbers mean? In the case of the. The in. Instead, this number refers to the year , the year these rounds were officially adopted by the United States military.

Then there are cartridges with designations resembling complex math problems. To break down the structure of this cartridge designation, the first number refers to the diameter of the projectile. In this case, 7. Caliber generally refers to handguns, rifles, and ammunition. Shotguns are a little different. We generally measure the barrel diameter of a shotgun in gauges. The number of lead balls this size that add up to one pound in weight is the gauge of the shotgun.

For example, it takes twelve lead balls the size of a 12 gauge shotgun bore to weigh a single pound. The exception to this rule is the. Although, the. Because caliber is typically measured in inches, understanding how inches compare to millimeters is a big help. This will also help you convert caliber to millimeters and vice versa. Consider this a basic firearms math lesson. If you look at a standard grade school ruler, you can easily see that each centimeter is divided into ten equal segments.

Each of these tiny hash marks measures one millimeter. If you compare the centimeter side of the ruler to the inches side, you can also observe that one inch is equal to 2. I cheated and used my math super powers. To convert caliber to millimeters, multiply the measurement in inches by Conversely, to convert millimeters to inches, divide the diameter in millimeters by For the mathematically challenged, you can just plug numbers into this handy online conversion calculator.

Typically, you can see the caliber of the firearm stamped right there it. Modern cartridges use smokeless powder, which can cause much greater pressures than old-fashioned black powder. In the example here, there are several things to point out. In this made it the most powerful handgun in the world, but then the.

To top it all off, there is an inconsistent way of referring to different calibers in conversation. The world of caliber naming conventions is a strange and wonderful thing that can make your head spin. Please enable JavaScript in Your Browser JavaScript is not currently enabled in your browser and due to this our site will not work as it should.

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Please add " opticsplanet. Variety of Ammo Cartridges, Calibers, and Bullets. Model 70 in. Marked ". Magazine Not A Clip. Clip Not A Magazine. Gallery Gun Marked for. Tap Tap to Zoom. About the Author. Visit Author Page. More Resources. Bullet Sizes vs. Bullet Sizes Bullet Caliber Gun Caliber Chamber For starters, we need to clear up some commonly misused terms and some terms that are used interchangeably.

It is commonly misused because people mean to refer to cartridges. Bullet sizes simply refer to the dimensions of the projectile by diameter, length, and weight in grains. Bullets are reloading components , used by handloaders who want to make their own ammunition using specialized reloading equipment.

This is because the employees deal with reloaders who really are just looking for the projectiles, and they deal with people who are new to firearms and are really just looking for live ammunition. It is made up of a bullet, powder, casing shell , and primer.

There are a lot of oddities like this in gun lingo. Bullet Caliber : This refers to the diameter of the bullet. You can have many different firearms that use the same caliber of bullets from Ballistics but have considerably different cartridges. Revolvers and pistols were used and are still in use with armies around the world. Firearms such as the AR are the latest in a long line of weapons that have gone from military to civilian use.

Guns are just much deadlier than they used to be. All modern firearms have internal mechanisms to prevent accidental firing. The most common is the safety. At its most basic, it is a lever that, once flipped, blocks the firing pin from dropping on a cartridge primer. Other mechanisms are less intrusive and are meant to prevent accidental discharge in the event the gun is dropped or mishandled.

The Colt MA1 and the Springfield XD both have grip safeties, levers that must be pressed when the gun is held properly for the gun to fire.

The Glock pistol has a safety on the tip of the trigger itself, ensuring that a finger must be on the trigger for the gun to fire. Sometimes people forget a gun is loaded.

Sometimes the weapon was loaded without their knowledge. If someone hands you a firearm, it is always a good idea to assume it is loaded. It is also a good idea to visually inspect the gun for a round in the chamber, even if you just saw someone else do it.

They might have missed something. Guns should always be pointed in a safe direction when handled. This goes for whether the gun is unloaded or loaded.

This sounds blindingly obvious. The fact is, a shocking number of people new to firearms immediately find their trigger fingers gravitating to the trigger. To people new to guns, it just seems like the place where the index finger is supposed to go.

If the person holding the gun is surprised, jolted, pushed, or shoved, his or her finger could reflexively squeeze the trigger, discharging the weapon before it is properly aimed. Aiming a gun with eyes focused on the target, a shooter develops tunnel vision.

This makes potential safety hazards between you and your target hard to spot until the very last moment. Furthermore, bullets can travel for miles beyond your target before gravity brings them down.

Only shoot in areas where you know with certainty that the entire potential path of the bullet is safe. Guns are inherently dangerous and must therefore be handled with extreme caution and care. Type keyword s to search. Today's Top Stories. A colonist stands guard with matchlock while others built a fort at Jamestown, Virginia, Getty Images. Firearms: An Illustrated History. DK amazon. Berrett-Koehler Publishers amazon. The Illustrated World Encyclopedia of Guns.

Lorenz Books amazon. A Remington Sportsman 78 bolt-action rifle. Michel Delsol Getty Images.