Originally Posted by
BarnesX.308
It's slightly faster because they case is more efficient. The shorter and wider case allows the powder to burn more completely and over a shorter span. So, they can develop full velocity in shorter barrels than the longer cases.
it may be more efficient, but loaded to the same pressure the larger case capacity creates more gas, which makes more velocity, no way can the wsm make more velocity than the 7 RM, cubic inches makes horsepower no matter how ya look at it
RR