I have had good results using it with my .243
I intend to try it in my .338 next.
I really like the fact that Alliant is now designing powders for specific calibers, not just a new or different burn rate as other manufacturers seem to do. Focusing on developing the powder for the best performance in a given cartridge will benefit hand loaders by minimizing wasted dollars spent on powders that don't work well for your gun.
I beat you to the punch on that one!
I worked up a load for my .338 WM using RL#17 and it turned out so GOOD I purchased an additional 5 lbs of it so I'd have the same lot #
2867 fps / 24 inch barrel - @ 4061 ft lbs of energy using a 225 grain Hornady SP made one BIG ragged hole at 100 yards.