Wow. No help what so ever Huh? I'm new here but most folks would at least give a favorite power for theirs and maybe a low starting load. I've just reloaded some for my new 20" PBR but haven't made it to the range yet. I researched it and loaded some with three different powders. Vargant, RL15, and IMR 4895. These should three good choices. I hope to get to the range this Thursday or Friday. I'll let you know more then.
My PBR likes SMK 168 gr and 40.5 gr of VARGET. But recommending a reload is like telling a guy if blondes, brunettes or redheads are better. Each rifle has its own likes and dislikes and you can't "force" a reload to perform well in it.
In other words, the answer to "what reload for my PBR" is a silly question. The rifle will like what the rifle likes.
This link has a lot of information, including the Sierra load map as a .pdf. I am using 41.5 of IMR 4064 and 168 SMK in a 20" PBR, with good results.
I am a beginning reloader, though a long-time shooter. I just wish I started reloading earlier. I don't think I save any money (LOL), but I do get much better ammunition than I can purchase for the same money. It has given a whole new dimension to shooting.