LAST EDITED ON Oct-17-10 AT 08:56PM (MST)[p]I have killed the majority of deer and antelope, 30+, with the 117 gr. Sierra gameking. The preformance was outstanding, but that was in a 25-06 that launches the bullet several hundred feet per second less then the 257 mag.
I would worry about bullet blow up on closer shots when using that bullet in the 257 mag. The other bullet I used in the 25-06 was the Nosler partition and that would be the one I would use in the 257 mag. or a bullet built tough like it.
RELH