What is WMR Ammo?
WMR, also known as.22 Winchester Magnum Rimfire, is a type of rimfire cartridge designed by Winchester Ammunition in the 1960s. It was created to be a higher-powered alternative to the popular.22 LR cartridge. In this article, we will delve into the history, characteristics, and usage of WMR ammo, as well as its applications and benefits.
What is WMR Ammo Made Of?
WMR ammo is composed of the following components:
• Casing: A rimfire cartridge case, typically made of brass, with a rimmed rim to ensure proper ignition.
• Primer: A standard rimfire primer, located on the rim of the casing, which is struck by the firing pin to initiate the ignition.
• Propellant: A powder charge, typically a smokeless propellant, designed to produce the desired pressure and velocity for the.22 WMR cartridge.
• Bullets: A.22 caliber projectile, usually made of lead or copper-plated lead, with a wad punch or hollow point design.
• Base: The base of the bullet is crimped onto the casing to prevent it from coming loose during firing.
Characteristics of WMR Ammo
WMR ammo has the following key characteristics:
- Velocity: WMR ammo typically has a higher velocity than.22 LR ammo, with average velocities ranging from 1,400-2,200 ft/s (427-671 m/s).
- Energy: WMR ammo has higher kinetic energy than.22 LR ammo, with an average of 150-220 ft-lbs (203-299 J).
- Range: WMR ammo has a longer effective range than.22 LR ammo, typically up to 150-200 yards (137-183 m).
- Accuracy: WMR ammo is generally more accurate than.22 LR ammo, due to its higher muzzle velocity and more consistent chamber pressure.
- Hunting suitability: WMR ammo is suitable for hunting small and medium-sized game, including rabbits, hares, and rodents.
Usage of WMR Ammo
WMR ammo is primarily used for the following purposes:
- Hunting: WMR ammo is used for hunting small and medium-sized game, taking advantage of its increased velocity and kinetic energy over.22 LR ammo.
- Plinking: WMR ammo is used for recreational target shooting, including plinking and casual range use, due to its increased range and accuracy over.22 LR ammo.
- Competition shooting: WMR ammo is used in some competitive shooting disciplines, such as NRA Silhouette and IPSC, where its increased velocity and kinetic energy provide a competitive edge.
Advantages and Disadvantages of WMR Ammo
Advantages:
- Increased range: WMR ammo has a longer effective range than.22 LR ammo, making it ideal for hunting and target shooting at longer distances.
- Increased kinetic energy: WMR ammo has more kinetic energy than.22 LR ammo, making it more effective at taking down small and medium-sized game.
- Increased accuracy: WMR ammo is generally more accurate than.22 LR ammo, due to its higher muzzle velocity and more consistent chamber pressure.
Disadvantages:
- Noise: WMR ammo is louder than.22 LR ammo, due to its higher velocity and more potent propellant charge.
- Explosive sound: WMR ammo can produce an explosive sound upon firing, due to the rapid expansion of the gas generated by the propellant charge.
- Expensive: WMR ammo is generally more expensive than.22 LR ammo, due to its higher performance and specialized design.
Comparison to.22 LR Ammo
The following table compares the characteristics of WMR ammo to.22 LR ammo:
| Characteristic | WMR Ammo | .22 LR Ammo |
|---|---|---|
| Velocity | 1,400-2,200 ft/s | 900-1,300 ft/s |
| Energy | 150-220 ft-lbs | 80-130 ft-lbs |
| Range | Up to 150-200 yards | Up to 100 yards |
| Accuracy | High | Medium to High |
Conclusion
WMR ammo is a high-powered rimfire cartridge designed to provide increased velocity, kinetic energy, and accuracy over.22 LR ammo. Its advantages, including increased range and accuracy, make it suitable for hunting, plinking, and competition shooting. However, its disadvantages, including noise, explosive sound, and cost, should be carefully considered by shooters.
