OK, so who has built one of these? If so, what action (other than MS) did you use to accomodate the goofy head size? Thanks...

U can use a Carcano action. I kid U not. In Fact the 6.5 X52 Carcano also makes a dandy little deer rifle. The largest mule deer I ever killed was with a sporterized Carcano. Six point western measurement. roger

The 6.5mm and 7.35mm Carcanos and 7.62x39mm share that head size.