Lead ?

[Kurt]

Once again, thanks Kurt for posting that 40-65 Cast. So the chamber to bore angle is 45degrees and the Lead 1.5 degrees if I'm following correctly So would it be a mistake to use a throat reamer to make that a gentler angle, much like your 40-65? I’m not in a rush but like to ponder ahead. I don’t want to plant any seeds in my brain that would spoil the chamber for black powder.

No my chamber transition is 4 degrees/1.5 degree compound. 1.5 degrees on the lead, 4 degrees in the throat.

There is nothing wrong the way the Browning BPCR chamber is, they shoot just fine as is. My chamber was bad the way the factory chambered it and I corrected it with a throating reamer I had made.
Kurt