Jim, now that you've shot some jacketed through it to "clean out the burrs", I'd shoot the cast & not worry about it unless it becomes troublesome to clean.
leading usuallu occurs when we try & drive cheap swaged lead bullets too fast. They are great for low velocity plinking rounds, but I try & keep them under 1,000fps. Faster than that & I like the hardcast. For hunting, I use 320 hardcast with gas-checks. I push mine 1300 fps+ in my S&W .44 mag revolver with no leading problems. I've shot the same bullet in my .444 Marlin Contender @ over 2,000fps with no leading problems.
There will always be some lead residue, bit it usually cleans easily.
That's all my opinion based on my limited experience.