Gun Barrels: How Do They Work?

by
posted on October 24, 2017
barrels.jpg
A gun barrel is a metal tube through which hot, rapidly expanding propellant gases convert stored chemical energy to kinetic energy by accelerating a bullet, shot swarm or other mass to a velocity. While this may seem simple, modern gun barrels are the result of over 600 years of continuous technological development. Although little more than a tube with one end closed, a gun barrel represents a complex blend of chemistry, physics, metallurgy, engineering and ballistics. In rifles and handguns, the barrel is the single most important factor in determining accuracy. In shotguns, the barrel controls the tightness and quality of the pattern.

Gun barrels also influence the physical characteristics of firearms such as overall length, weight and recoil, as well as handling qualities such as balance, swing and pointing.

All gun barrels have a cylindrical hole running completely through them, known as the bore, in which the bullet or shot swarm travels as it is accelerated. In rifles and handguns, the bore has spiral lands and grooves, which are called "rifling." As the bullet travels down the bore, the lands grip the bullet by engraving its outer surface, causing it to spin on its axis so it will stabilize in flight...much like the "spiral" of a football's travel. Rifling may either be left-hand twist or right-hand twist, with the latter being most common. Most shotguns have smooth bores with a constriction about 2 inches from the muzzle, which is known as the "choke." At the rear end of the barrel is an enlarged area for the cartridge, called the "chamber." The tapered portion at the front of the chamber is called the leade or throat in a rifle, and the forcing cone in a shotgun. Finally, the front end of the barrel is called the muzzle, and the chambered end of the bore is called the crown. 

Stay tuned for next week, when we'll cover how rifling works.

Latest

Franchi Momentum All Terrain Elite
Franchi Momentum All Terrain Elite

New Guns 2025: Franchi Momentum All-Terrain Elite Rifle in Verdant Camo

For hunters who appreciate accuracy and do-it-all performance in a more compact design.

New Guns 2025: Rossi R95 Triple Black Lever-Action Rifle

Lookin' chunky! This solid, compact lever gun offers modern features for the modern shooter.

New Gear 2025: MTM Case-Gard Suppressor Case

It helps save your hearing, so doesn't it deserves a case as nice as your gun's?

New Gear 2025: Silencer Central Banish Speed K Titanium Suppressor

Strong enough for law enforcement, but lightweight and affordable enough for you.

New Guns 2025: EAA 2311 Witness Double-Stack Pistol

The Year of the Double-Stack continues with this low-recoil, high-capacity 1911-style handgun.

New Guns 2025: Charter Arms Double Dog Revolver

We double-dog dare you to try out this two-cylinder revolver!

Interests



Get the best of NRA Family delivered to your inbox.