To expand on Brad's short and (as usual) precise comment, the 7x57 is one of the rounds left behind by the decision of most "modern" rifle manufacturers that all cartridges should fit in magazines of about 2.8", 3.35" or 3.6". And there aren't all that many modern actions between 2.8" and 3.6".
The 7x57 is designed for an overall length of about 3" or a little longer. This makes it a dispossessed orphan.
My own 7x57 (my last and perfect 7x57 after owning at least a dozen) is made on the "short" Montana 1999 action, which has a magazine about 3.1" long. It weighs exactly 8 pounds with a 4x33 Leupold in Talley lightweight mounts, and was built by Serengeti Rifles (now Kilimanjaro Rifles) with one of their 3-layer laminated stocks that can hardly be told from straight wood. It has been dinged somewhat from use, as I've taken a pile of animals from springbok to moose with it over the past half-dozen years, but is completly reliable and still very accurate.
Of course, the same thing could be done with a bunch of other cartridges, but this rifle has been there and done that.
