I also have a Scout V2 6.5 CM ordered and should be here any day now! From all I've read you can figure 200 - 300 fps less in the 14inch barrel. I'm basing this on an article I read which reported the velocity loss by the inch from 27 to 16 inches.
Shooting 120 grain bullets showed a loss of 233 fps and shooting 140 grainers showed a loss of 153. These figures may be a little off due my terrible memory but I think they are close. Remember you will still lose a little from 16 inches to 14 inches also.