Can anyone tell me what velocities I can expect with a 300 SMK out of a standard .338 WinMag? I have a remington SS-DM and these bullets will fit nicely in the magazine. My only alternative is to go to a .300 Weatherby. Not even a .340 Weatherby will fit the detachable mag. I know they are supposed to be the same case OAL, but when trying factory ammo in the mag, the .300's will fit while the the .340's won't. They're slightly longer right out of the box.