What he said - lead is the way to go.
You can go much slower without sticking a bullet in the bore. I like liquid alox as a second lube in carbines (to compensate for a longer bore). I would probably go with with a 124-130 grain RN-FP and hand weighed charges charges of Clays or Bullseye. A 147 grainer may not be stable at 50-100 yards if it's going too slow.