lengths .22 Short .22 Long The .22 Long Rifle may also be used in firearms chambered for the obsolete .22 Extra Long. Usage Today, rimfire rounds are mainly used for hunting small pests, for sports shooting, for plinking, and for inexpensive training. The .22 LR is the choice for several shooting events: biathlon, bullseye, plus divisions of benchrest shooting, metallic silhouette and pin shooting, most high school, collegiate, Boy Scouts of America, Project Appleseed, 4H shooting events, and many others. It is also used in the precision Rifle and Pistol shooting events at the Olympic Games. Good quality rimfire ammunition can be quite accurate. The main advantages are low cost, low recoil, low noise and high accuracy-to-cost ratio. The main disadvantage is its low power; it is better suited for use on small game and other small animals. As a defensive cartridge, it is considered inadequate by many, though the small size allows very lightweight, easily concealable handguns which can be carried in circumstances where anything larger would be impractical. Despite their limitations, people can use .22 LR pistols and rifles for defense, and they are common simply because they are prevalent, inexpensive, and widely available. Most semi-automatic rifles firing .22 LR cartridges will often only work properly when firing standard or high velocity rimfire ammunition, as the low recoil of subsonic rounds is insufficient to cycle the weapon's action. Rifles with manual actions do not have this problem. Due to the low bolt thrust of the .22 LR cartridge, most self-loading firearms chambered for the cartridge use the direct blowback operation system. The tiny case of the .22 LR and the subsonic velocities (when using subsonic ammunition) make it well suited for use with a firearm suppressor (also known as silencers or sound moderators). The low volume of powder gases means that .22 LR suppressors are often no larger than a bull barrel; the Ruger 10/22 and Ruger MK II are common choices, because of their reliability and low cost, and the resulting product is often nearly indistinguishable from a bull barrel model (although weighing far less). Where firearm suppressors are only minimally restricted, a .22 LR firearm with a suppressor is often favored for plinking, as it does not require hearing protection or disturb the neighbors. Local government agencies sometimes use suppressed rimfire weapons for animal control, since dangerous animals or pests can be dispatched in populated areas