I received the Lyman Cast Bullet Handbook today and was a bit surprised at some of the loads for 357 Magnum. With HS-6, one of my favorites, the starting load for a 158 gr LSWC(#358156) was 8.8 gr and max at 9.7 gr. The 158 gr #358665 was 9.2 and max 10.2. These are all pretty much on par with the old Speer #8 manual that everyone thinks is a time bomb as their max load was 10 gr with the same powder and weight bullet.
Velocities are right up there and without a hard bullet of maybe BHN 15 or 18 I'm sure leading would be pretty bad. Still, I'd like to try some of these soon. I don't know where you'd find a BHN 15 bullet but Missouri Bullet makes an 18 for magnum loads. Come to think of it, I believe Rimrock makes a BHN 15 LSWC.
Velocities are right up there and without a hard bullet of maybe BHN 15 or 18 I'm sure leading would be pretty bad. Still, I'd like to try some of these soon. I don't know where you'd find a BHN 15 bullet but Missouri Bullet makes an 18 for magnum loads. Come to think of it, I believe Rimrock makes a BHN 15 LSWC.