The 300 NORMA Magnum (short for "Norma Magnum") is a powerful and versatile cartridge designed for long-range shooting and hunting. It was developed by the Swedish ammunition manufacturer Norma in collaboration with the American gunmaker U.S. Optics, and is based on the .338 Lapua Magnum case, necked down to .308 inches.

The 300 NORMA Mag offers excellent accuracy and ballistics, with a flat trajectory and high velocity. It can propel heavy bullets with high sectional density and ballistic coefficients, making it an ideal choice for long-range hunting of large game such as elk, moose, and bears. Additionally, the cartridge has been adopted by several military and law enforcement agencies for long-range sniping and anti-personnel applications. Overall, the 300 NORMA Mag is a powerful and effective cartridge that has gained a strong following among hunters, precision shooters, and tactical operators.