As a general rule of thumb, figure a 20% increase in velocity over the listed pistol velocities.
My cowboy action load for 45 Colt was 7.0 Grains of W231/250 Laser Cast rnfp, and chrono'd right around 800 fps. The same load in my Marlin Cowboy gave 1000fps +/-.
I'v found about the same boost with other loads too - hotter ones with 300 grain hardcast/gc bullets and H110/W296.
vbshootingrange - IIRC you're load is giving around 1450 fps. In a 4 3/4" revolver, that'd give about 1150 fps fyi.
Last edited by OSOK; 04/29/08.
