I like partitions too, unfortunately I am wanting to find a "non lead" load to shoot everywhere since we have these stupid lead zones here in the land of fruits and nuts. I hunt more big four legged creators out of california than I do here, but want a load that I can use anywhere.
The 20" 300 win mag is no louder than a 24" Some loads have a noticable muzzle blast increase. Its a hunting rifle, I never notice either when i have the crosshairs on a critter.