Short and fat = efficient. Compare the 30-06 to the 308. The 308 hold about 47 grains with a bullet and the 06 hold about 63 grains of powder with a bullet in the case. With bullets of 175 grains and less, the 308 is only about 100 FPS slower than the 06 with much better inherent accuracy. Each case is the same diameter. The 06 is quite a bit longer.
One can make the same comparison to the wsm and the RUM. Large case differances, slight gains in performance. Now if you compare the 7mm wsm
vs the 7mm Rem mag, they about equal each other. The wsm will offer better accuracy potential and less recoil.
One of the benefits to shorter is that more of the actual primer flash reaches more of the powder. Thats one reason why they are so efficient and accurate.
[ 02-14-2004: Message edited by: meichele ]