I think the old swede and the 160 grain roundnose are a perfect match for big game. It won't win any speed contests but it doesn't really need to. I get excellent accuracy with this round and get around 2,500 ft/sec. As it compares to the 6.5/06, the 6.5x55 is up to a couple hundred ft/sec slower. As for 6.5 Rem Mag Remington at one time chambered it in the 600? I think but can't think of any current producers. There's also the 6.5 -284 or the 260 to choose from too. For me, I'm with Kliktarik - the 6.5x55 works better than most give it credit for and would be my choice.
