Based on the advice of various people here, I picked up a few M70 WSMs after having feeding issues with Remingtons.
The Win mag box allows you to run them long and throat them long. I'm building a 300wsm to run 200gr partitions at 2.96 and in my 7wsm I run loads at 2.96 as well but that is limited by throat length more than mag box. I did notice that at 2.98 COAL with the partitions, feeding got a little less slick. This might not be the case with a Berger or ELD-anything.
In two other custom rifles I had, 200gr partitions hit the lands at 2.93 and 2.94 when the chambers were freshly cut (ELDs were longer but I'd have to check my notes). At 2.90 COAL I seem to recall that I had no trouble fitting 67.5gr of 4831SC under a 200 partition, Norma brass.
