Can't help ya on the factory loads either, but a Lee die set can be had for $21-$31!!
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Mine shoots real good with +P loads at a little over 1900fps with 250gr jacketed bullets, I'd try the hotter loads like Cor-bon or Buffalo bore.
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Handloading for the Colt definitely has an advantage in that you can use the 250gr SST muzzleloader bullet to extend the effective range of the Colt to 175yds or so with no hold over and more that sufficient energy for deer at that range, maybe even a bit further, specially if the rifle is scoped.
Tim
http://www.gboreloaded.com/forums/index.php/topic,124487.msg1098436387.html#msg1098436387Trajectory for Custom .451 dia. (45 cal) 250 gr. SST at 1900 Feet per Second
At an Elevation Angle of: 0 degrees
Ballistic Coefficients of: 0.21 0.21 0.21 0.21 0.21
Velocity Boundaries (Feet per Second) of: 720 720 720 720
Wind Direction is: 0.0 o'clock and a Wind Velocity of: 0.0 Miles per hour
Wind Components are (Miles per Hour): DownRange: 0.0 Cross Range: 0.0 Vertical: 0.0
Altitude: 0 Feet with a Standard Atmospheric Model.
Temperature: 59 F
Data Printed in English Units
Range Velocity Energy Momentum Drop Bullet Path Wind Drift Time of Flight
(Yards) (Ft/Sec) (Ft/Lbs) (Lb-Sec) (inches) (inches) (inches) (Seconds)
0 1900.0 2003.6 2.11 0.0 -1.5 0.0 0.000000000
25 1813.0 1824.3 2.01 -0.31 0.64 0.0 0.040410915
50 1728.8 1658.9 1.92 -1.28 2.12 0.0 0.082775723
75 1647.7 1506.9 1.83 -2.98 2.88 0.0 0.127215091
100 1569.9 1367.9 1.74 -5.48 2.83 0.0 0.173850143
125 1495.7 1241.6 1.66 -8.86 1.9 0.0 0.222799891
150 1425.3 1127.5 1.58 -13.21 0.0 0.0 0.274174654
175 1359.1 1025.3 1.51 -18.64 -2.97 0.0 0.328070501
200 1297.5 934.4 1.44 -25.24 -7.12 0.0 0.384560653