I have had bbls. from 26" down to 22.5", my definite favourite is the Dakota 76 contour at .340" muzzle diameter at 23".
Shorter tubes do lose velocity and are also pretty loud, but, a 23" will run 250s at 2725 fps-mv, with 76-77 RE-22, a top load and an accurate one in all my rifles.
YMMV, but, if I wanted to shoot 200-210 bullets, I would run a .300 mag. and actually do this with my two .300s, however, I much prefer a .338WM to any .300 mag.
