A tactic for using the 'space ship killer broadside' to actually hit ships is to run at them aiming to pass just alongside and as your bow (the pointy end) loverlaps them fire. The rounds carry some of your momentum and a number will hit the target without going into orbit. Takes a while but you will sink the target eventually.
The orbit bit only appear to happen when there is actually something to hit alongside you!
It jsut so much easier to team up with at least 1 other player and let them do the killin while you hold the helm. Just remmeber to pass the points around