A Semi-automatic rifle is a rifle that fires one round each time the trigger is pulled. During World War II, Germany and the Soviet Union deployed semi-automatic rifles in limited scales, while the United States deployed the semi-automatic M1 Garand as their main service rifle. Semi-automatic rifles are generally used where accuracy is important for taking out targets rather than rapid firing and giving away one's position. Selective fire modes often include semi-automatic fire. The semi-automatic function is also a feature on battle rifles, and some sniper rifles. Generally, semi-automatic rifles have high power, but a low fire rate, in comparison to other weapons. Some people have built controllers which push the fire button much quicker than a human could, achieving deadly, though morally questionable, results (commonly called "mods"). Before using a semi-automatic weapon, one should take into consideration whether it has a Firecap or not. A firecap determines its maximum rate of fire.