Understanding the .22 WMR Cartridge
What is .22 WMR?
The AR-15. The name alone conjures images of a rifle that has become an American icon. Its modularity, adaptability, and the sheer variety of configurations have made it a favorite amongst shooters, hunters, and enthusiasts alike. From home defense to competitive shooting, the AR-15 platform offers something for everyone. But beyond the standard chamberings like .223 Remington and 5.56x45mm NATO, a world of possibilities opens up. Today, we’re diving into a fascinating variant: the .22 WMR AR-15. This isn’t your run-of-the-mill AR-15. It’s a rimfire rifle built on the AR-15 platform, a combination that offers a unique shooting experience.
The .22 WMR AR-15 presents a compelling option for those seeking a cost-effective, versatile, and potentially even more enjoyable way to experience the AR-15. This guide will explore everything you need to know about the .22 WMR AR-15, from its cartridge specifics and how it interacts with the AR-15 design to its pros and cons, allowing you to make an informed decision about whether this is the right firearm for you.
Before we delve into the rifle itself, let’s examine the cartridge that fuels it: the .22 Winchester Magnum Rimfire, often abbreviated to .22 WMR. This round, unlike the more common .22 Long Rifle (.22 LR), is a more potent rimfire cartridge. The .22 WMR wasn’t developed to be compatible with the standard AR-15.
The .22 WMR was initially designed in the late 1950s by Winchester. This was a step above its predecessor, the .22 Long Rifle, with much more power. Its primary purpose was to provide a higher-performance rimfire option for hunting small game. The cartridge’s design, with a larger case and a higher powder charge, allows it to deliver significant improvements in velocity, trajectory, and energy compared to the ubiquitous .22 LR.
One of the significant advantages of the .22 WMR is its increased velocity. A typical .22 WMR round will leave the muzzle traveling at speeds that far surpass those of a standard .22 LR. This higher velocity results in a flatter trajectory, meaning the bullet drops less over distance. This improved trajectory makes accurate shooting at extended ranges easier.
Furthermore, the .22 WMR offers better terminal ballistics. The higher velocity translates to more kinetic energy delivered to the target upon impact, resulting in greater stopping power. This makes the .22 WMR a more suitable choice for hunting small game, like rabbits, squirrels, and even varmints, compared to the .22 LR.
A key factor for many shooters is ammunition availability and cost. While .22 WMR ammunition might be slightly more expensive than .22 LR, it’s generally available at most gun stores and online retailers. The increased power and the fact that it isn’t nearly as common as .22 LR often leads to a higher cost per round. It is important to keep the cost per round in mind when considering a .22 WMR AR-15.
However, the .22 WMR is not without its drawbacks. As mentioned, ammunition costs can be higher, which may be an important factor for those who shoot frequently. The .22 WMR, while more potent than the .22 LR, is still a rimfire cartridge, which has some limitations.
The .22 WMR AR-15 Platform
Compatibility
The .22 WMR, designed for bolt-action and lever-action rifles, is not automatically compatible with the AR-15 platform. The AR-15, typically built for centerfire cartridges, requires specific modifications to accommodate the rimfire .22 WMR round. This doesn’t mean you have to abandon your favorite rifle platform though.
One of the key aspects of a .22 WMR AR-15 is the upper receiver. The upper receiver is typically either bought pre-made or built for .22 WMR. The upper receiver houses the bolt carrier group and barrel.
Another critical component is the bolt carrier group (BCG). A dedicated .22 WMR BCG is designed to handle the specific mechanics of rimfire cartridges. This BCG needs to have the proper firing pin and extractor to reliably extract and eject fired casings.
The barrel is crucial to overall performance. Barrels are made with specific twists and length. Many manufacturers provide barrels specifically designed for the .22 WMR, paying close attention to the internal dimensions to accommodate the cartridge. These barrels often have a slightly different bore diameter than barrels designed for .22 LR.
The magazine is also an important component. Standard AR-15 magazines are not compatible with the .22 WMR. Specialized magazines are designed specifically for this cartridge. These magazines have different follower designs and can be made of varying materials for long-lasting durability.
The .22 WMR AR-15’s operation is similar to that of a standard AR-15 but relies on the unique characteristics of the .22 WMR cartridge. The BCG moves back and forth to reload. After firing, the blowback system pushes the bolt back, ejecting the spent casing and chambering a new round.
Advantages and Disadvantages of the .22 WMR AR-15
Advantages
The .22 WMR AR-15 offers a compelling set of features that should be considered carefully. The combination of the AR-15 platform and .22 WMR cartridge, provides a unique set of benefits. However, it is equally important to understand the potential drawbacks.
One of the most significant advantages of the .22 WMR AR-15 is its cost-effectiveness for training. Compared to the centerfire AR-15s chambered in .223 Remington or 5.56mm NATO, the .22 WMR offers significantly lower ammunition costs. This means that you can spend more time at the range without breaking the bank. The .22 WMR AR-15 is a good way to practice fundamentals of shooting.
The .22 WMR AR-15 is an excellent choice for small game hunting. The .22 WMR provides a balance of velocity, energy, and relatively flat trajectory, that makes it very effective for hunting small game at reasonable ranges. The platform also allows for a wide range of accessories, such as scopes, which helps in a variety of hunting scenarios.
Lastly, the .22 WMR AR-15 is enjoyable to shoot. The AR-15 platform is known for its modularity and ergonomic design, making it comfortable for a variety of shooters. The .22 WMR, while more powerful than .22 LR, still has very manageable recoil.
Disadvantages
However, the .22 WMR AR-15 has some notable disadvantages. Ammunition costs are higher, especially when compared to .22 LR. This will be a significant factor for those who shoot regularly.
Reliability can also be a factor. Rimfire cartridges, generally, are more susceptible to issues like misfires and failures to extract than centerfire cartridges.
Finally, the .22 WMR AR-15’s range and terminal performance are still limited compared to larger caliber AR-15s. At longer ranges, the .22 WMR loses velocity and energy, potentially impacting its effectiveness.
Comparing Rimfire Options
.22 WMR vs .22 LR
To fully understand the .22 WMR AR-15, it is important to put it in context. Here are a few comparisons to provide additional insight.
The most obvious comparison is the .22 WMR AR-15 to a .22 LR AR-15. The .22 LR is the more common rimfire cartridge. The ammunition is much cheaper than the .22 WMR, and is thus, more ideal for training. However, the .22 WMR offers a higher velocity and flatter trajectory, along with better terminal ballistics. The .22 WMR also provides increased range and greater effectiveness for hunting small game.
Rimfire Rifles
A second comparison is to other rimfire rifles, such as bolt-action rifles and lever-action rifles. The .22 WMR is very popular, and therefore, there are many options available. The AR-15, with its semi-automatic action, provides faster follow-up shots than bolt-action rifles.
Choosing the Right Rifle
Factors to Consider
If you are considering a .22 WMR AR-15, a few key considerations can help you to choose the right platform for your needs. The intended use is one of the first factors to consider. Whether you plan to hunt, plink, or train can influence the configuration.
The budget is always an important factor. The cost of a .22 WMR AR-15 will vary depending on components and the brand. It is important to balance the cost with the performance and features that you desire.
Finally, reliability and manufacturer reputation are also critical. Researching different manufacturers and reading reviews can help in making an informed decision.
Safety and Maintenance
Safety Precautions
Safety should always be the top priority when handling any firearm. Before handling any .22 WMR AR-15, make sure you understand safe gun handling procedures. Always treat every firearm as if it is loaded.
Cleaning and Maintenance
Cleaning and maintenance are essential to ensure the longevity and reliability of your .22 WMR AR-15. Proper cleaning is especially important. The rimfire cartridges can produce more residue than the centerfire counterparts.
Conclusion
The .22 WMR AR-15 is a niche offering on the AR-15 platform, but it offers some unique features. The .22 WMR cartridge combines the power of the AR-15 design and delivers a solid performance, particularly for hunting and target shooting. The .22 WMR AR-15 is great for those who want to enhance their range experience.
The .22 WMR AR-15 provides a distinct shooting experience. The platform is an enjoyable option for shooters looking to enhance their shooting or training. It is a very versatile option with many options.
If you’re seeking a new experience and a unique rimfire option, consider the .22 WMR AR-15. Research different manufacturers and configurations and decide if the .22 WMR AR-15 is right for you.
