The purpose of practice is to get better scores yes? Loading the shotgun, rifle past 50, and transitions are three of the largest chunks of time people typically donate to their competition in 3Gun. Practicing draws and reloads is pretty good for pistol, but won't get you much, until you are bumping over say 80% at majors. There is not a good source for these drills yet. The students I have in classes, I tell them to practice these dryfire...
1. Off hand to 150 yards
2. Odd and traditional rested rifle positions with a heart rate at 150% of resting.
3. Load 1, 2, 4 rounds of dummy rounds, then 4-2s and 2-4s.
4. Transitions: On and off tables, from slings, dump and go, dump and shoot.
If you spend 2 hours a week on those over the winter, and are a typical 50% shooter, you will shoot at 70% or better in 2015.
Steve Anderson's books, at the best, might get you 5%. Get the big chunks of time first, then perfect.