You're right, the Montana action "did not minic 98 Mauser gas handling," but the bolt shroud was flanged, which probably diverts gas away from the shooter's face as much as any factor in the 98's design.
Winchester somehow missed this, among other things. Even the later CRF Model 70s, which have what is supposedly a gas-block on the left side of the bolt, let a LOT of gas blow right back into the shooter's face.
