Scott, are you looking for a light load, or a load using a light bullet? Assuming the latter, the 100 GR is about as low as one should go in the .284 bore diameter, because of low sectional density and BC. What do you want to use it for? I once cooked up a 120 GR load in the 7X57 to use on small Central Texas whitetails. No matter what I tried, I could not get much over 3100 feet per second out of this weight of bullet. In addition, it caused ENTIRELY TOO MUCH meat damage, so I went back to what I had been using before, a 140 grain at about 2900 fps from a Ruger M77 with 22" barrel. The 140 is a good weight in the 7X57.

Larry