This is .280 Ackley Improved Corbon 140gr. DPX Ammo. Corbon's ultimate big game hunter load features the Barnes Triple Shock X bullets. This combination ensures high velocity, greater terminal ballistics, and deep penetration for the largest, most dangerous game. This is new manufactured ammo by Corbon that is brass cased, boxer primed, and non corrosive. It has an all copper jacketed projectile that will not stick to a magnet. The velocity is 3000 fps and 2799 ft lbs. This ammo packed 20rds. per box.