The M1903A3 is a bolt-action rifle that was used by the United States military during World War II. It is an updated version of the earlier M1903 rifle, featuring a simpler rear sight and a more streamlined production process. The rifle is chambered for the .30-06 Springfield cartridge, which provides excellent accuracy and range. The M1903A3 was designed for infantry use and became known for its reliability and effectiveness in combat. It was primarily used by snipers and marksmen, contributing to its reputation as a highly regarded firearm in American military history.