I had a CZ 550 with the full-length stock and 21" barrel for a while, and spent part of one range session comparing the velocities of several loads from it and my CZ 550 rifle with 23.6" barrel. As I recall, the biggest difference in velocity between the two was 88 fps, with most loads less than 50 fps. One load actually averaged slightly faster from the shorter barrel.
Do you recall which one? Trying to develop some loads for the FS with AB
