So finally I decided it is time to work up a few loads with the GDHP bullets. After doing some research it seems that these will not expand when loading them in 38spl, and even in 357mag, it seems they do not expand much. I looked at the Lucky Gunner test results, and at 1245fps (2" barrel) they did not expand, but at 1403fps (4" barrel), it expanded to .52". My Ruger SP101 has a 3" barrel, so it seems I will have to push it very hard to get it to expand and maybe use them as Zombie loads. Is it even worth it to try and get these to a decent velocity, or should I just have fun and see what accuracy I can get out of them? Anybody has any experience with these bullets in 38spl or 357mag?