3.5 to 3.8 grains of Bullseye, under a 158 grain LSWC. I've tried 3.5, 3.6, 3.7 and 3.8 grains in my K-frames. All shoot very well. 3.6 and 3.7 grains seem to be the best of the lot......so I usually load 3.6 grains.