 This makes the 7mm Remington Magnum case with its 6.89 mm long neck better suited for loading long heavier bullets.On the other hand, the proportions of 7mm Winchester Short Magnum promote good internal ballistic efficiency that allows the 7mm Winchester Short Magnum to fire shorter lighter bullets at slightly higher muzzle velocities while using less propellant than the classically proportioned 7mm Remington Magnum.The commercially rarer 7mm Remington Short Action Ultra Magnum cartridge, a rebated rim bottlenecked centerfire short magnum introduced in 2002, is probably the other closest ballistic twin of the 7mm Remington Magnum.