 The 7mm Remington Short Action Ultra Magnum is considerably shorter and fatter and has a steeper shoulder angle and a longer neck (7.90 mm) than the 7mm Remington Magnum.This makes the 7mm Remington Short Action Ultra Magnum better suited for loading long heavier bullets.These 21st century ballistic twin short fat magnum cartridges can handle Pmax piezo pressure according to the C.I.P.