Hi Mike,
The 20 V-Max is a super bullet in the .17 Hornet, and there are several good powders. For several years used 12.0 grains of Accurate 1680 as my standard load, for around 3600 from the 22-inch barrel of my CZ, but recently tried the new Hodgdon CFEBLK and accuracy is similar, but velocity's almost 200 fps faster. If you can't get those, 12.0 H4198 (AR2207) also gets around 3600, but in my rifle isn't quite as accurate as 1680 of CFEBLK. But as I mentioned earlier, spherical powders flow easiest through the tiny neck.
