Speaking of efficiency, years back I remember reading one of the gun writer scribes writing that of all the center-fire cartridges at the time, the .300 Savage got the highest bullet weight and velocity from the least amount of powder. Only the rimfire .22 LR was more efficient power to powder. That might have changed with the advent of the Creedmoor and others, but that .300 Savage and the Model 99 were both way ahead of their time.
