sniper was in the area, the location of the sniper could be determined after the sniper had fired a few shots. The Allies used their own snipers in the Pacific, notably the U.S. Marines, who used M1903 Springfield rifles. Common sniper rifles used during the Second World War include: the Soviet M1891/30 Mosin–Nagant and, to a lesser extent, the SVT-40; the German Mauser Karabiner 98k and Gewehr 43; the British Lee–Enfield No. 4 and Pattern 1914 Enfield; the Japanese Arisaka 97; the American M1903A4 Springfield and M1C Garand. The Italians trained few snipers and supplied them with a scoped Carcano Model 1891. Training Military sniper training aims to teach a high degree of proficiency in camouflage and concealment, stalking, observation and map reading as well as precision marksmanship under various operational conditions. Trainees typically shoot thousands of rounds over a number of weeks, while learning these core skills. Snipers are trained to squeeze the trigger straight back with the ball of their finger, to avoid jerking the gun sideways. The most accurate position is prone, with a sandbag supporting the stock, and the stock's cheek-piece against the cheek. In the field, a bipod can be used instead. Sometimes a sling is wrapped around the weak arm (or both) to reduce stock movement. Some doctrines train a sniper to breathe deeply before shooting, then hold their lungs empty while they line up and take their shot. Other doctrines assert that exhausting the lungs results in an accelerated heart rate and suggest only a partial exhale before firing. Some go further, teaching their snipers to shoot between heartbeats to minimize barrel motion. Accuracy The key to sniping is accuracy, which applies to both the weapon and the shooter. The weapon should be able to consistently place shots within tight tolerances. The sniper in turn must use the weapon to accurately place shots under varying conditions. A sniper must have the ability to accurately estimate the various factors that influence a bullet's trajectory and point of impact, such as range to the target, wind direction, wind velocity, altitude and elevation of the sniper, and the target and ambient temperature. Mistakes in estimation compound over distance and can decrease lethality or cause a shot to miss completely. Snipers zero their weapons at a target range or in the field. This is the process of adjusting the scope so that the bullets' points-of-impact are at