Had a pounds of Red Dot left over from shotgun loading, so used it in my lite plinking 30-06 loads...worked well as Red Dot is "fluffy" (larger volume for the weight). IS a very fast powder, but would use as little as 5gr. and as much as 12gr. and good results.
Never did get ball to shoot real well, but .311 or .312" ball did decently well at very short range with as little as 2gr. of red Dot. I'd cast them. Trick seems to be to NOT SIZE the fired case at all, just deprime and prime, leaving the case neck it's fired/expanded size. Charge with powder (2gr.). Press the ball down FLUSH with the case mouth. Smear lube over the ball (which being flush with the case mouth, has room around the sides of the ball for lube).