Keep your eye on how hard they extract. If the initial pull on the lever is hard and you get any primer cratering, back off. What does Hodgon say for a max load?

Whats the main reason for a goal of 1,000 fps? I would just pick a load that is accurate, minimal recoil and is clean. If thats 800 fps or 1200 fps, no matter.

If you want to drive 158s faster, get a slower powder. Keep in mind, the faster you push lead, the more likely you are to get lead buildup.