The 300 Remington Ultra Mag (300 RUM) was released in 1999 and became an instant hit among big game and long range hunters.  This massive magnum shoots flat, hits hard and is capable of taking all of North America's big game species. The 300 RUM makes an excellent choice for all species worldwide short of the biggest beasts abroad.  Our 300 Remington Ultra Magnum ammunition comes in twenty (20) round boxes.