Read, Read & Read!
The above books are great resources. I shoot BPC in several calibers. By experimentation and elimination you will find what your rifle likes best.
I think you will find that any hollow base bullet will never give you the accuracy of a flat base. The Lee 405 bullet in the flat base is a good starting point. The 500gr Govt and the 525 Postell are also good choices. See if you can get a small amount of a number of different bullets before you go investing in molds. Some of us have molds for a specific caliber that add up to more than the rifle cost!
Go slow. SPG lube is good. Harlows is also good. Easy to make your own also.
Ive been shooting BPCR for 20 years and enjoy its challenges.
Did I say Read, Read & Read