For five-stage bouncing you'll need 5 separate entries:
$Name:  Gun
$Name:  Gun#2
$Name:  Gun#3
$Name:  Gun#4
$Name:  Gun#final
Make them exactly the same, except for one difference in the $Flags section:
Have in "Gun" flag section:  spawn Gun#2 1
in "Gun#2" :  spawn Gun#3 1
"Gun#3":  spawn Gun#4 1
"Gun#4":  spawn Gun#final 1
and don't put a "spawn" flag in the "Gun#final"
if you were doing 6-stage, then you could omit one stage and have alternating between Gun and Gun#2 (I think).  Don't quote me on this since I'm just speculating, but that's a close approximation.
Also, there's no way to control what angle the projectile's going to spit out, except for how you point the ship, and its position relative to the target.
[This message has been edited by Bushwacker (edited 06-10-2001).]