Buy Norma Tac .22 LR 40GR Online Australia
Introduction
The .22 Long Rifle or simply .22 LR or 22 (metric designation: 5.6×15mmR) is a long-established variety of .22 caliber rimfire ammunition originating from the United States. It is used in a wide range of rifles, pistols, revolvers, and submachine guns.
In terms of units sold, it is by far the most common ammunition in the world today. Common uses include hunting and shooting sports. Ammunition produced in .22 Long Rifle is effective at short ranges, has little recoil, and is cheap to purchase. Therefore, making it ideal for plinking and marksmanship training. American firearms manufacturer J. Stevens Arms & Tool Company introduced the .22 Long Rifle cartridge in 1887. The round owes its origin to the .22 BB Cap of 1845 and the .22 Short of 1857. It combined the case of the .22 Long of 1871 with a 40-grain (2.6 g) bullet, giving it a longer overall length, a higher muzzle velocity, and superior performance as a hunting and target round, rendering the .22 Extra Long cartridge obsolete. The .22 LR uses a heeled bullet, which means that the bullet is the same diameter as the case, and has a narrower “heel” portion that fits in the case. It is one of the few cartridges that are accepted by a large variety of rifles and handguns.
The .22 LR cartridge is popular with both novice shooters and experts. Its minimal recoil and relatively low noise make it an ideal cartridge for recreational shooting, small-game hunting, and pest control. .22 LR cadet rifles are commonly used by military cadets and others for basic firearms and marksmanship training. It is used by the Boy Scouts of America for the rifle shooting merit badge.
The low recoil of the cartridge makes it ideal for introductory firearms courses. Novice shooters can be surprised or frightened by the noise and recoil of more powerful rounds. Beginners shooting firearms beyond their comfort level frequently develop a habit of flinching in an attempt to counter anticipated recoil. The resulting habit impedes correct posture and follow-through at the most critical phase of the shot and is difficult to correct. With high recoil eliminated, other errors in the marksmanship technique are easier to identify and correct.
Available for this round are AR-15 upper receivers and M1911 slide assemblies. Many handgun manufacturers have an upper pistol conversion kit to make it shoot .22 LR ammunition. These conversions allow shooters to practice inexpensively while retaining the handling characteristics of their chosen firearms (with reduced recoil and muzzle blast). Additionally, .22 LR cartridge conversion kits allow practice at indoor ranges which prohibit high-power firearms. Owners of guns that use gas systems, such as AR-15 sport style rifles, normally avoid firing non-plated .22 LR cartridge ammunition, as the use of non-plated ammunition may cause lead-fouling of the gas-port inside the barrel and costly gunsmithing procedures. This can usually be mitigated by swapping the conversion kit for the standard bolt carrier group and firing several full-powered rounds to clear the gas port and tube of any accumulated lead fouling. While not 100% effective, the extremely hot incandescent gasses produced by centerfire rifle ammunition will help to clear any lead fouling from the .22 LR ammunition.
A wide variety of .22 LR ammunition is available commercially, and the available ammunition varies widely both in price and performance. Bullet weights among commercially available ammunition range from 20 to 60 grains (1.3 to 3.9 g), and velocities vary from 575 to 1,750 ft/s (175 to 533 m/s). .22 LR is the least costly cartridge ammunition available. Promotional loads for plinking can be purchased in bulk for significantly less cost than precision target rounds. The low cost of ammunition has a substantial effect on the popularity of the .22 LR. For this reason, rimfire cartridges are commonly used for target practice.
.22 LR cartridges are commonly packaged in boxes of 50 or 100 rounds, and are often sold by the ‘brick’, a carton containing either 10 boxes of 50 rounds or loose cartridges totaling 500 rounds, or the ‘case’ containing 10 bricks totaling 5,000 rounds. Annual production is estimated by some at 2–2.5 billion rounds. The NSSF estimates that a large percentage of the US production of 10 billion cartridges is composed of .22 LR. Despite the high production figures there have occasionally been shortages of .22 LR cartridges in the contiguous United States, most notably during the U.S. ammunition shortage of the late 2000s and early 2010s.
The .22 LR is effective to 150 yd (140 m), though practical ranges tend to be less. After 150 yds, the ballistics of the round are such that it will be difficult to compensate for the large “drop”. The relatively short effective range, low report, and light recoil have made it a favorite for use 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. A contributing factor in rifles is the transition of even a high-velocity cartridge projectile from supersonic to subsonic within 100 yd (91 m). As the bullet slows, the shock wave caused by supersonic travel overtakes the bullet and can disrupt its flight path, causing minor but measurable inaccuracies.
When zeroed for 100 yards (91 m), the arc-trajectory of the standard high-velocity .22 LR with a 40 gr (2.6 g) bullet has a 2.7-inch (69 mm) rise at 50 yards (46 m), and a 10.8-inch (27 cm) drop at 150 yards (140 m). A .22 LR rifle needs to be zeroed for 75 yards (69 m) to avoid overshooting small animals like squirrels at intermediate distances.
As a hunting cartridge, rimfires are mainly used to kill small game up to the size of coyotes. Although proper shot placement can kill larger animals such as deer or hog, it is not recommended because its low power may not guarantee a humane kill. In 2013, an elephant was killed by multiple shots from a .22 LR rifle.
Because a .22 LR bullet is less powerful than larger cartridges, its danger to humans is often underestimated. In fact, a .22 LR bullet is easily capable of killing or injuring humans. Even after flying 400 yards (370 m), a .22 bullet is still traveling at about 500 ft/s (150 m/s). Ricochets are more common in .22 LR projectiles than for more powerful cartridges as the combination of unjacketed lead and moderate velocities allows the projectile to deflect – not penetrate or disintegrate – when hitting hard objects at a glancing angle. A .22 LR bullet can ricochet off the surface of water at a low angle of aim. Severe injury may result in a person or object in the line of fire on the opposite shore, several hundred yards away. A .22 LR bullet is capable of traveling 2,000 yards (1,800 m), which is more than 1 mile (1.6 km).
Rimfire bullets are generally either plain lead with a wax coating (for standard-velocity loads) or plated with copper or gilding metal (for high-velocity or hyper-velocity loads). The thin copper layer on plated bullet functions as a lubricant reducing friction between the bullet and the barrel, thus reducing barrel wear. Plating also prevents oxidation of the lead bullet. Lead tends to oxidize if stored for long periods. On a plain lead bullet, oxide on the bullet’s surface can increase its diameter enough to either prevent insertion of the cartridge into the chamber or – with high-velocity rounds – cause dangerously high pressures in the barrel, potentially rupturing the cartridge case and injuring the shooter; for that reason, standard and subsonic cartridges usually use a wax lubricant on lead bullets.
The traditional .22 rimfire cartridges (BB, CB, short, long, extra long, and long rifle) differ in construction from more modern cartridges in the way the bullet is constructed and held in the case. Bullets for traditional .22 rimfires are the same outside diameter as the case but are constructed with a narrower cupped “heel” on the base of the bullet which is inserted into the case. The case mouth is then crimped around the heel, leaving exposed the majority of the bullet-bearing surface that contacts the barrel of the gun. The bearing surface of .22 rimfire bullets is often lubricated and the surface is exposed to contamination. This was a common design in the early black powder cartridge era.
In later cartridges, including the .22 WRF and .22 WMR rimfires and modern centerfires, the bullet body is a uniform diameter and the bearing surface is inserted completely within the neck of the cartridge case, held in place by tension from the case neck around the bullet bearing surface (in some cartridges the case mouth may also be crimped into a cannelure (groove) in the bullet). The heeled bullet cartridge is considered weaker than the uniform-diameter bullet cartridge which encloses the bearing surface of the bullet within the cartridge neck. Overall reliability of heeled bullet rimfire ammunition is high, but it is lower than the reliability of most centerfire ammunition.
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