OK - I admit to liking the .270 WSM. The 7MM Rem Mag is a great round as well. But in the same barrel length (22") and at the same pressure; the WSM (or 7MM RSAUM) will develop a little more speed than a 7 Rem Mag due to its shorter, fatter powder column. The case capacity of these two is very close, with a very slight advantage going to the 7 Mag, but not enough to overcome the better efficiency of the WSM case. And as for accuracy, ask any benchrest shooter about short fat cases . . . .

PS: Glad you have such an exceptionally accurate 7 Rem Mag.