I am not really working up a load as much as playing in the back yard. I used my bench, but offhand is more fun. I can always go back to the bench. I am wondering about the lightweight barrel bouncing off the rest. I used a foam pad rest at the entry pipe, but it still didn't seem to do right. Fun is what it is all about. My deer shots are usually less than 50yds. If I can shoot near the big bull black at that distance, I will be in minute-of-deer accuracy.
Smylee: The combination is a snug(not tight) fit in the .575 bore, and .535s are readily available. It will thumb start but is a good fit. A .570 won't fit. The recovered patches aren't blown so it must be about right. I think I am mostly sight limited. The rear groove is wide, and it is hard to get a good sight picture. Elevation is hard to repeat. If you look at some other holes in that target there is some vertical stringing on the centerline.