That I did not know, though I have a 6,5x68 loaded with RWS 93-grain bullets, (going a little faster!), which I consider would be ideal for Chamois. It's flat shooting and so helps eliminate some of the issues of range estimation. But I can see how the 6,5x57 would have been seen in the same light in the 1930's as it doesn't take a 160-grain bullet to knock down a Gamsbock. In fact, the more I think about the lighter weight of the standard length 6,5x57 action in the mountains, the more I like the idea.