.22 Long Rifle
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The .22 Long Rifle rimfire cartridge is a long established variety of ammunition, and in terms of units sold is still by far the most common in the world today. The cartridge is often referred to simply as a ".22" and various rifles, pistols, revolvers, and even some smoothbore shotguns have been manufactured in this caliber. The .22 Long Rifle and its derivative cartridges use a heeled bullet, which means that the bullet is the same diameter of the case, and has a narrower "heel" portion that fits in the case.
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Performance
The .22 LR is inexpensive, often costing less than two US cents per cartridge. It is effective within 150 meters (after 150 meters the ballistics of the round are such that the large "drop" will be difficult to compensate for). The relatively short effective range, low report and light recoil has made it a favourite as a target practice cartridge. The accuracy of the cartridge is good, but not exceptional; various cartridges are capable of the same or better accuracy. The effectiveness of this cartridge is often underestimated. The newest commercial rimfire, the .17 Mach 2 is a .22 LR based cartrdige, firing a light .17 caliber bullet at a much higher velocity than the .22 LR. Many .22 LR firearms are being sold chambered for the .17 Mach 2, and modifying a .22 LR to shoot .17 Mach 2 often requires just a barrel change. The .17 Mach 2 extends the effective range significantly over the .22 LR. The disadvantage of the .17 Mach 2 is the price, which is several times that of than the .22 LR, and the increased noise of firing caused by the higher muzzle pressure and supersonic bullet.
As a hunting cartridge, the .22 LR is mainly used to kill small varmints such as rats and squirrels. It is also effective on rabbits closer than 75 meters. For greater range or larger game a more powerful cartridge should be used to ensure a clean kill. Examples include larger rimfire rounds such as the .22 WMR, .17 HMR, or any centrefire catridge. Like any bullet, the .22 LR is nonetheless dangerous and is capable of killing humans and other large animals.
Variants
There are a variety of different types of .22 Long Rifle (or ".22 LR") loads. They are sometimes divided into 3 categories; subsonic, standard and hyper-velocity (or ultra-velocity). The subsonic rounds have a muzzle velocity of 330 m/s or less and are often equipped with an extra heavy, 2.9-3.9 gram bullet. The standard rounds have a supersonic muzzle velocity and a "normal" weight, 2.5-2.6 gram bullet. The so-called hyper-velocity bullets may have a muzzle velocity of 450-550 m/s and this velocity is partially due to the light bullets they use. The bullets are usually around 1.9-2.2 grams in weight. The bullets themselves are in all cases usually either solid or hollow-point bullets.
Special shot cartridges, usually loaded with #12 shot (see shotgun shell) in this caliber have been made and these are ideal for pest control at very short ranges. Such rounds will either have a longer brass case that is crimped closed, or a translucent plastic "bullet" that contains the shot and shatters upon firing. In a specially made .22 bore shotgun, the shotshells can be used for short range skeet shooting and trap shooting at special, scaled down clay targets.
.22 LR High Velocity
A somewhat improved .22 LR cartridge that increases the bullet velocity with a stronger charge and copper plating on the bullet. The thin copper layer on the bullet functions as a lubricant and reduces the friction between the high velocity bullet and the barrel, thus reducing barrel wear. It also has a oxidation preventing effect on the lead bullet. Lead tends to oxidise if stored over long periods of time and as a result of this, the bullet's diameter increases to a level that might both prevent the insertion of the cartridge in the chamber and might cause the pressure in the barrel to rise to a dangerously high level. The increase in pressure may lead to the case rupturing and potential danger to the shooter. Standard and subsonic cartridges tend to use a type of wax for the same purpose.
Usage
Today .22 Long Rifle ammunition is mainly being used for hunting small pests, for sports shooting and for cheap training. Its main advantages are low cost, low recoil and low noise. Its main disadvantage is its anemic performance.
Although .22 LR pistols and rifles are used for Olympic shooting events, less than 5% of the world's sport shooting competitions are held in .22 LR.
Specifications
- Case length: .595 in
- Muzzle velocity:
- 2.56 g (40 gr) lead: 330 m/s (1082 ft/s) .22 LR
- 2.33 g (36 gr) copper plated lead: 405 m/s (1328 ft/s) .22 LR High Velocity
Compatible Ammunition
The .22 Long rifle uses a straight walled case. Depending upon the type and the feed mechanism employed, a firearm which is chambered for .22 Long Rifle may also be able to safely chamber and fire the following shorter rimfire cartridges:
The .22 Winchester Magnum Rimfire, also called .22 Magnum or .22 WMR, uses a different case, which has a significant taper and does not use a heeled bullet. Firing a .22 Long Rifle or derivative in a .22 WMR firearm will likely result in a potentially dangerous case rupture.
See also
External links
- Outland Sales (http://www.outlandsales.com/22data.html)