What is Rimfire Ammunition?

A popular pick for firearms enthusiasts, but what exactly is it?

When it comes to different types of ammunition, there are different types such as rimfire and centerfire; but not everyone knows what these things are. Rimfire ammunition holds a distinct place in the world of firearms and shooting sports. Characterized by its unique ignition mechanism, rimfire ammo is both a favorite among beginners and a reliable choice for seasoned shooters. 

We are going to take a look into the specifics of rimfire ammunition, exploring its history, mechanics, types, and applications.

What is Rimfire Ammunition?

Rimfire ammunition is a type of firearm cartridge where the primer—the chemical compound that ignites the gunpowder—is located in the rim of the casing. This contrasts with centerfire ammunition, where the primer is housed in the center of the cartridge base, something that you may see with your standard AK and AR rounds as an example. 

When the firing pin strikes the rim of a rimfire cartridge, it crushes the rim and ignites the primer compound, which then ignites the gunpowder, propelling the bullet forward.

Where did Rimfire Ammo Come From?

The invention of rimfire ammunition dates back to the mid-19th century. The first successful rimfire cartridge was the .22 Short, developed by Smith & Wesson in 1857 for their Model 1 revolver. This innovation marked a significant advancement in firearm technology, providing a reliable, self-contained cartridge that eliminated the need for separate percussion caps. 

Over time, rimfire ammunition evolved, leading to the development of various calibers and types that catered to different shooting needs and preferences.

Mechanics of Rimfire Ammunition

The construction of rimfire cartridges is relatively simple but ingenious and effective. The key components are:

1. Case: Typically made of brass, the case houses the primer, gunpowder, and bullet. In rimfire cartridges, the rim is thin and hollow, allowing it to be crushed by the firing pin.
2. Primer Compound: Located in the rim, the primer is a sensitive explosive material. When struck, it generates a small explosion that ignites the gunpowder.
3. Gunpowder: A chemical propellant that burns rapidly, creating gases that expand and propel the bullet out of the barrel.
4. Bullet: The projectile, usually made of lead or lead-coated with another metal, which is expelled from the firearm when the gunpowder ignites.

This design contrasts with centerfire ammunition, where the primer is a separate component placed in the center of the cartridge base. The rimfire mechanism is simpler and less expensive to produce, contributing to the widespread popularity of these cartridges.

Types of Rimfire Ammunition

The most common and widely used rimfire cartridge is the .22 Long Rifle (LR), renowned for its versatility and low cost. However, other notable rimfire calibers include:

• .22 Short: Used primarily in small, concealable firearms and for target shooting. Despite its short range and low power, it remains popular for specific applications.
• .22 Long: An intermediate round between the .22 Short and .22 LR, offering a balance of performance and size.
• .22 Winchester Magnum Rimfire (WMR): Offers higher velocity and energy, suitable for small game hunting and varmint control. The .22 WMR provides greater stopping power and accuracy at longer ranges compared to the .22 LR.
• .17 HMR (Hornady Magnum Rimfire): A newer, high-velocity round designed for precision and small game hunting. The .17 HMR is known for its flat trajectory and high accuracy, making it a favorite among varmint hunters and target shooters.

Each type of rimfire ammunition serves specific purposes, catering to different needs and preferences of shooters. The variety within the rimfire family allows users to select the most appropriate cartridge for their intended use, whether it be target practice, hunting, or competitive shooting.

When to Use Rimfire Ammunition

Rimfire cartridges are popular for various applications due to their low cost, mild recoil, and relatively low noise. 

Key uses include:

• Training and Education: Ideal for beginners due to their manageable recoil and affordable price, allowing for extensive practice without significant expense. Rimfire ammunition provides a comfortable and accessible way for new shooters to learn and improve their skills.
• Target Shooting: Favored in both informal plinking and competitive shooting sports. The accuracy and consistency of rimfire cartridges, particularly the .22 LR, make them a staple in shooting ranges and competitions.
• Hunting: Suitable for small game and pest control, not necessarily big game. The .22 LR and .22 WMR are commonly used for hunting small animals like rabbits, squirrels, and other pests. The precision and effectiveness of rimfire rounds make them reliable tools for managing wildlife populations.
• Recreational Shooting: Rimfire ammunition is perfect for casual shooting activities, providing hours of enjoyment at a minimal cost. Whether shooting at cans, paper targets, or reactive targets, rimfire cartridges offer a fun and economical option for all ages.

Not Self Defense?

Rimfire ammunition may not be the best for self defense, as they are typically smaller calibers. While rimfire ammunition is better than nothing in a defense scenario, there are better calibers for this.

Advantages and Limitations of This Ammunition

Advantages of Rimfire Ammo:

• Cost-Effective: Rimfire ammunition is generally less expensive than centerfire counterparts. This affordability allows shooters to practice more frequently without incurring high costs.
• Low Recoil: Makes it easier to handle, especially for new shooters and those sensitive to recoil. The gentle recoil of rimfire cartridges promotes better accuracy and comfort during extended shooting sessions.
• Versatility: Suitable for a wide range of firearms and purposes, from handguns to rifles. Rimfire ammunition's adaptability makes it a practical choice for various shooting disciplines and activities.

Limitations With Rimfire Ammo:

• Limited Power: Rimfire cartridges have lower power compared to centerfire, making them unsuitable for large game hunting or self-defense. The reduced stopping power of rimfire rounds limits their effectiveness in scenarios requiring higher energy output.
• Reliability: Rimfire ammunition can be more prone to misfires due to the primer distribution in the rim. While generally reliable, the occasional misfire is a known drawback of rimfire cartridges, necessitating quality control and proper handling.

Best Place to Get Ammo Near You

When looking for just about any type of ammunition, Shoot Angry Inc. is the place to go. One of the top gun stores in Douglassville Pennsylvania, they can ship anywhere!

Conclusion

Rimfire ammunition continues to be a cornerstone in the world of shooting sports and small game hunting. Its simplicity, affordability, and ease of use make it an enduring choice for shooters of all skill levels. Whether for training, recreational shooting, or hunting, rimfire cartridges offer a reliable and cost-effective solution for a wide array of shooting activities. From the iconic .22 LR to the precise .17 HMR, rimfire ammunition provides an accessible and enjoyable shooting experience for enthusiasts worldwide.