what caliber gun do they shoot in the biathlon in the olympics
Biathlon The biathlete carries a small-bore rifle, which weighs at least 3.5 kilograms (7.7Â lb), excluding ammunition and magazines. The rifles use .22 LR ammunition and are bolt action or Fortner (straight-pull bolt) action. The rifle must weight more than 3.5 kilograms. Each rifle holds 4 magazines with 5 rounds each. Addtional rounds can be kept on the stock of the rifle for a relay race.
.243 Winchester The .243 produces a velocity of 2,960 feet (902.21 m) per second with a 100-grain (6.6 gram) projectile from a 24-inch (610 mm) barrel. Commercially loaded .243 ammunition is available with bullet weights ranging from 55 grains (3.6 g) up to 115 grains (6.8 g). Twist rate of the barrel is the major deciding factor in which bullets to use, 1:10 being the most popular as it is sufficient to stabilize up to 100-gr. bullets. However, for very low drag-profile and bullets heavier than 100 grs., a 1:8 or 1:7 (for 115-gr. VLD bullets) is necessary.