I was pretty lazy with my load and didn't do any work up with the Afterburner. I took Mark's recommendation and started with load data for the 150gr TTSX, compared that to my experience with other copper bullets with minimal bearing surface (CE, Hammer, GS Custom), and took a chance on a load. I was able to match the listed velocities for the 150gr TTSX using the same powder, but going about 1.0gr over the max charge weight I found listed. That's not the best way to do it, but I've shot enough copper bullet to have a decent idea of what to expect. I'll say that case head expansion, primer appearance, case extraction/bolt lift on that load were all comparable to the Remington factory ammunition I was shooting on the same trip. I'm sure I could run the velocity up higher, but I'm not sure what I'd really gain. The ES/SD is great, the velocity is nothing sneeze at, and the groups look really good so far.