This is what I use in a M1911. Shoots well, and Bullseye is the original powder in the 45ACP, been used for almost a century and still going strong.
I taper crimp the case mouth to 0.469".
As for load development, with the powders I use, half a grain. My best load was at 4.5 grains. See how the velocity changes with weight. My goal was to develop a safe, accurate load just at 800 fps with a 230 lead bullet.
Kimber Custom Classic M1911
230 gr LRN 4.5 grs Bullseye Mixed Brass WLP
21-Jun-06 T = 97 °F
OAL 1.250" taper crimp .469"
Ave Vel = 805.2
Std Dev =11.4
ES=54.08
High=836.9
Low=782.8
N =32
230 LFN Bull-X 3.5 grs Bullseye Mixed Brass WLP
OAL 1.20" taper crimp .469"
8-Jan-06 T = 61 °F
Ave Vel = 643.6
Std Dev = 14.07
ES = 63.63
High = 679.9
Low = 616.3
N = 32
shot a little high Pistol cycled each shot
230 LFN Bull-X 4.0 grs Bullseye Mixed Brass WLP
OAL 1.20" taper crimp .469"
8-Jan-06 T = 61 °F
Ave Vel = 715.9
Std Dev = 11.45
ES = 48.32
High = 742.9
Low = 694.8
N = 32
shot a little low
230 gr LRN 4.0 grs Bullseye Mixed Brass WLP
OAL 1.250" taper crimp .469"
29-Jan-06 T = 68 °F
Ave Vel = 698.8
Std Dev = 10.19
ES = 36.33
High = 713.5
Low = 677.1
N = 28
Little High = put close point of aim V. Accurate