I have a question concerning velocity and the amount of powder it takes . How is it that a 300RUM shooting a 200 gr. bullet max out at approximately 3000fps, but a 338 EDGE based on the same case can shoot a 300 gr bullet at 2850fps. They both share the same parent case, same case capacity, but the 338 shoots a bullet 50 % heavier and only gives up 150fps in velocity. I assume it has something to do with working pressure and the time duration of the bullet in the barrel,but still don't understand how this works, if they are operating at the same pressures. Granted the EDGE velocity is based on a 30" barrel versus a 26" barrel on the 300RUM, but I am curious as to the corelation of powder charge and derived velocity. Would someone please explain this.