What Is 22 caliber

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Last updated: April 15, 2026

Quick Answer: A 22 caliber refers to a firearm or cartridge with a bullet diameter of approximately 0.22 inches (5.6 mm). The most common type is the .22 Long Rifle, introduced in 1887, known for low recoil and affordability. It is widely used for target shooting, small-game hunting, and training.

Key Facts

The .22 Long Rifle cartridge was introduced in 1887 by the J. Stevens Arms & Tool Company
22 caliber bullets typically measure 0.22 inches (5.6 mm) in diameter
The .22 LR can achieve velocities up to 1,640 feet per second (500 m/s)
Over 2 billion .22 LR rounds are produced annually worldwide
22 caliber firearms are used in Olympic shooting events since 1908

Overview

The term '22 caliber' refers to firearms and ammunition that fire bullets with a diameter of approximately 0.22 inches (5.6 mm). It is one of the most widely used calibers globally due to its low cost, minimal recoil, and versatility across shooting disciplines. The most popular variant, the .22 Long Rifle (.22 LR), has been a staple in recreational shooting and training for over a century.

Originally developed for rimfire ignition, 22 caliber cartridges are commonly used in rifles, pistols, and even some submachine guns. Their low noise and manageable report make them ideal for backyard ranges and indoor shooting facilities. Because of their widespread availability and low price, they are often the first choice for new shooters and marksmanship programs.

Introduced in 1887: The .22 Long Rifle was developed by J. Stevens Arms & Tool Company and quickly became the dominant small-caliber round for civilian use.
Bullet diameter: 22 caliber bullets measure exactly 0.224 inches (5.6 mm), allowing compatibility across various firearms platforms.
Rimfire design: Unlike centerfire cartridges, 22 caliber rounds use rimfire ignition, where the firing pin strikes the base's rim to ignite the primer.
Low recoil: The .22 LR generates only about 1 foot-pound of recoil energy, making it ideal for beginners and youth shooters.
Cost-effective: Ammunition costs average $0.07 to $0.15 per round, significantly cheaper than centerfire alternatives.

How It Works

The 22 caliber operates through a simple yet effective rimfire mechanism, where the firing pin strikes the edge of the cartridge base to ignite the propellant. This design keeps manufacturing costs low and ensures reliable function in a wide range of firearms.

Ignition method: Rimfire cartridges contain priming compound distributed around the base rim, which detonates when struck by the firing pin.
Propellant charge: A typical .22 LR round contains 3.5 to 4 grains of smokeless powder, generating pressures up to 24,000 psi.
Muzzle velocity: Standard velocity rounds travel at 1,050 feet per second, while hyper-velocity variants can exceed 1,640 fps.
Effective range: Accurate up to 150 yards, though most shooting occurs within 50 yards due to bullet drop and wind drift.
Subsonic options: Some .22 LR rounds travel below the speed of sound (1,126 fps) to reduce noise, useful for suppressed firearms.
Reliability: Due to simple internal mechanics, 22 caliber firearms have high reliability but are sensitive to dirt and misfires if ammunition is old.

Comparison at a Glance

The following table compares common 22 caliber cartridges based on performance metrics:

Cartridge	Bullet Weight (grains)	Muzzle Velocity (fps)	Energy (ft-lbs)	Primary Use
.22 Short	29	1,045	70	Target practice, pistols
.22 Long	29	1,100	75	Obsolete, limited use
.22 Long Rifle	40	1,200	137	Hunting, training, plinking
.22 WMR	45	1,550	210	Small-game hunting
.22 Hornet	45	2,650	745	Varmint control, rifles

While the .22 LR dominates in popularity, other variants like the .22 WMR (Winchester Magnum Rimfire) offer higher velocity and energy for extended range. The .22 Hornet, though centerfire, is sometimes grouped with 22 caliber discussions due to bullet size. Each variant serves a specific niche, from casual plinking to serious varmint control.

Why It Matters

The 22 caliber remains a cornerstone of firearms culture due to its accessibility and adaptability across user levels and applications. Its role in safety training and competitive shooting ensures continued relevance in modern times.

Training standard: Most U.S. military and police cadets begin marksmanship training with .22 LR firearms due to low recoil and cost.
Olympic discipline: 22 caliber rifles are used in ISSF 50-meter events, a staple of the Summer Olympics since 1908.
Small-game hunting: Effective on rabbits, squirrels, and pests, with over 60% of rural U.S. households using .22s for this purpose.
Survival utility: Lightweight and high-capacity, .22 rifles are standard in emergency kits and bug-out bags.
Gun safety education: Programs like 4-H and NRA youth camps rely on 22 caliber firearms to teach responsibility and marksmanship.
Global production: Over 2 billion .22 LR rounds are manufactured annually, making it the most produced cartridge in history.

From backyard plinking to Olympic gold, the 22 caliber continues to shape how people learn, compete, and responsibly use firearms. Its enduring legacy is a testament to simple, effective design.