<P> Called military patrol, the combination of skiing and shooting was contested at the Winter Olympic Games in 1924, and then demonstrated in 1928, 1936, and 1948, but did not regain Olympic recognition then because the small number of competing countries disagreed on the rules . During the mid-1950s, however, the biathlon was introduced into the Soviet and Swedish winter sport circuits and was widely enjoyed by the public . This newfound popularity aided the effort of having the biathlon gain entry into the Winter Olympics . </P> <P> The first Biathlon World Championship was held in 1958 in Austria, and in 1960 the sport was finally included in the Olympic Games . At Albertville in 1992, women were first allowed in the Olympic biathlon . </P> <P> The competitions from 1958 to 1965 used high - power centerfire cartridges, such as the . 30 - 06 Springfield and the 7.62 × 51mm NATO, before the . 22 Long Rifle rimfire cartridge was standardized in 1978 . The ammunition was carried in a belt worn around the competitor's waist . The sole event was the men's 20 kilometres (12 mi) individual, encompassing four separate ranges and firing distances of 100 metres (330 ft), 150 metres (490 ft), 200 metres (660 ft), and 250 metres (820 ft). The target distance was reduced to 150 metres (490 ft) with the addition of the relay in 1966 . The shooting range was further reduced to 50 metres (160 ft) in 1978 with the mechanical targets making their debut at the 1980 Winter Olympics in Lake Placid . </P> <P> In 1948, the Union Internationale de Pentathlon Moderne et Biathlon (UIPMB) was founded, to standardise the rules for the biathlon and the modern pentathlon . In 1993, the biathlon branch of the UIPMB created the International Biathlon Union (IBU), which officially separated from the UIPMB in 1998 . </P>

What kind of guns do they use in the olympics