from what I've been seeing, 5 and 10 sps work, but 10 sps empties the clip in the same amount of time, everything in between tends to skip a little bit.
Easy way: take the 8.9 sps from the black ops section, open it in the macro editor, click the grey gear, and mess around with the speed multiplier. Although 5sps (speed multiplier of 0.5) seems to be the best one for all semi-automatic weapons as far as I can tell.
