Components of Ammunition
A single piece of ammunition, made up of the bullet, casing, powder, and primer.
How Does Firing Ammunition Work?
How is Ammunition Measured?
Ammunition is measured by the bullet’s diameter, which is known as “caliber”. The caliber can be measured in both inches and millimeters (mm).
Depending on where it was invented, ammunition is measured in millimeters or inches. 9mm ammunition originates in Europe, whereas the .40 caliber was invented in the United States.
Ammunition for a pistol corresponds to the pistol caliber, so you will use 9mm ammunition for a 9mm pistol.
Popular Semi-Automatic Pistol Ammunition Calibers
- .380 ACP:
- This small round is known as the “three-eighty” and is a popular choice for small pistols.
- This caliber is the most popular and widely used worldwide.
- .40 S&W:
- Larger and slower than 9mm, with more recoil.
- .45 Auto:
- Slightly larger and slower than .40 caliber, with a bit more recoil.
- .45 GAP:
- GAP stands for “GLOCK Automatic Pistol”. This caliber rivals the firepower of the .45 Auto, but is shorter, allowing it to fit into a more compact semi-automatic pistol.
- Has greater range and is faster than the .45 Auto.
- .357 Auto:
- Slightly longer than the .40 caliber, and known for accuracy and stopping power.