self-defense load of buckshot contains 8–27 large lead pellets, resulting in many wound tracks in the target. Also, unlike a fully jacketed rifle bullet, each pellet of shot is less likely to penetrate walls and hit bystanders (though in the case of traditional 00-Buck, overpenetration of soft and hard targets may be an issue). It is favored by law enforcement for its low penetration and high stopping power. On the other hand, the hit potential of a defensive shotgun is often overstated. The typical defensive shot is taken at very close ranges, at which the shot charge expands no more than a few centimeters. This means the shotgun must still be aimed at the target with some care. Balancing this is the fact that shot spreads further upon entering the target, and the multiple wound channels are far more likely to produce a disabling wound than a rifle or handgun. Sporting Some of the most common uses of shotguns are the sports of skeet shooting, trap shooting, and sporting clays. These involve shooting clay discs, also known as clay pigeons, thrown in by hand and by machine. Both skeet and trap competitions are featured at the Olympic Games. Hunting The shotgun is popular for bird hunting (called "game-shooting" in the UK, where "hunting" refers to hunting mammals with a pack of hounds), it is also used for more general forms of hunting especially in semi-populated areas where the range of rifle bullets may pose a hazard. Use of a smoothbore shotgun with a rifled slug or, alternatively, a rifled barrel shotgun with a sabot slug, improves accuracy to or more. This is well within the range of the majority of kill shots by experienced hunters using shotguns. However, given the relatively low muzzle velocity of slug ammunition, typically around 500 m/s (about 1600 feet per second), and the blunt, poorly streamlined shape of typical slugs (which cause them to lose velocity very rapidly, compared to rifle bullets), a hunter must pay close attention to the ballistics of the particular ammunition used to ensure an effective and humane kill shot. At any reasonable range, shotgun slugs make effective lethal wounds due to their tremendous mass, reducing the length of time that an animal might suffer. For example, a typical 12-gauge shotgun slug is a blunt piece of metal that could be described as an 18 mm (.729 inch) caliber that weighs