I had a similar thought in putting a Leupold VX-2 6x18x40 on a rifle for load development. That worked out pretty well.
However, I ran into a time crunch, could not replace the scope with a lower power, and took it coyote hunting. While it worked, and I killed a coyote at just over 200yds while it was on 6x, I am going to replace it with a lower power scope, and probably sell this one.
The groups I can get with a 3x9 or 4x12 don't appear to be different than the 6x18.
