If you are relatively new to shooting sports and self-defense, you may have heard talk about cartridges or rounds and centerfire or rimfire. But you may not know the difference between them or if one is “better” than the other. Simply put, these cartridges propel their bullets in different ways. Here are their histories and pros and cons.

Rimfire History

The first rimfire cartridge, which later became known as the .22 Short, was also the first successful self-contained cartridge to be developed. Prior to the introduction of the .22 Short and other rimfire calibers, a single round of ammunition consisted of a charge of powder, a lead ball, a cloth patch to separate the ball from the powder and a percussion cap to fire the complete round. In Colt black powder percussion revolvers of the time, the cylinder chambers served as de facto cartridge cases for the individual components. While the assembled components could be fired rapidly from the Colt revolving cylinder, reloading the cylinder was quite slow.

The .22 Short was introduced just prior to the Civil War in Smith & Wesson’s tiny Model 1 seven-shot, single-action revolver. The Model 1 was produced from 1857 to 1882 and found great popularity with Union military officers as an emergency vest pocket pistol.

How Does a Rimfire Cartridge Work?

Rimfire cartridges of any caliber contain their priming compound all the way around the inside of the rim of the cartridge, hence the name. This allows rimfire cartridges to fire regardless of how they are positioned in the chamber … as long as they go in bullet-end first, of course.

To fire a rimfire round, the firing pin must quickly compress the bottom of the cartridge rim against the top of the rim, which is being held in place by the chamber. The top and bottom of the rim being slammed together by the firing pin is what detonates the priming compound. And the priming compound ignites the powder. The burning powder gases then force the bullet from the case, down the bore of the firearm and out of the muzzle. The system has worked extremely well for 165 years … but there is one issue with it.

For consistent and reliable ignition, the entire rimfire cartridge case needs to be made from brass thin enough and soft enough that the firing pin can compress the rim without puncturing it. Because of this necessary and delicate balancing act, only relatively low pressure/low power rimfire cartridges will function reliably.

Today’s rimfires are highly reliable. I consider the .22 LR and .22 Magnum rimfire cartridges a viable option for personal defense for those that can’t tolerate a lot of recoil. Of course, they are also extremely capable for recreational shooting, hunting and pest control.

Currently, 10 rimfire cartridges are still readily available ranging in size from .17 to .22. At one time there were rimfire cartridges as large as .58 caliber available. For a great reference on rimfire or centerfire cartridges of all types, I highly recommend a copy of Cartridges of the World by Gun Digest Books.

Centerfire Cartridges

One of the very first and most popular centerfire cartridges was the .44-40 Winchester. It was introduced for use in Winchester’s 1873 lever-action rifle — the gun that Won the West. The ’73 Winchester Rifle replaced the .44 Henry Rimfire cartridge and rifle.

The .44-40 cartridge exploded in popularity because it was also chambered in handguns such as Colt’s Frontier Six-Shooter and S&W’s Model 3 single-action revolver. People on the frontier or remote farms and ranches appreciated the ability to use the same cartridge in their handguns and rifles, making resupply simpler.

However, the .44-40 achieved much of its popularity because of its centerfire ignition system. It propelled the bullet around 100 feet per second faster than the .44 Henry and from a shorter 20-inch barrel. This increase in power was made possible due to much stronger, solid-brass cartridge cases that contained the primer in their base. When the firing pin strikes that central primer, it too detonates. That ignites the powder in the cartridge case and sends the bullet down the barrel. All powerful modern cartridges are centerfire.

Centerfire cartridges are more expensive to manufacture than disposable rimfire rounds because the primer is an extra component. Therefore, many who own a centerfire handgun or rifle (say in 9mm) also own another one just like it in .22 caliber as an “understudy” gun. These can be used to train a new shooter for the 9mm, in place of a 9mm where noise and penetration are a concern or simply to save money during practice.

Wrap Up

Despite attempts to develop “more modern” cartridges — the Gyrojet Pistol System, which fired rocket cartridges or the Remington EtronX electronic primer ignition system — none were a success or a threat to conventional rimfire and centerfire cartridge systems. A rimfire firearm, especially in .22 Long Rifle is an essential arm every gun owner should also have access to. There is simply no practical substitute for these cartridge systems. A great philosopher once said, “if it ain’t broke, don’t fix it.”