I have never seen a live Sambar, but I have seen a LOT of American Elk. I understand they are about the same size.
I also have some experience with the 7X57 and the 7-08, which are ballistic twins as I load them.

I can tell you that a 160 or 175 gr Hornady, or better yet, Nosler Partition will kill any elk you hit through the chest from either shell.

The modern gun writes know that their first loyalty is NOT to the readers, but to those that pay the paychecks, which are the advertisers. They will go over the rails to get people to buy new guns, new scopes, new laser range finders, new new NEW!

But the fact is that the 7X57 with good bullets has a super good reputation in the game fields all over the world and it is as good as it ever was.

In fact with the bullets we have for it today it is better than any time in it's history.

It's not new.

But it is just fine.