Shooting vehicles out of guns like proj's

[tmowr250]

Ok so i made the magnum shoot out a warthog which was cool but gets annoying and stupid because it just kinda appears beside you (often kills you). So I screwed around with properties for a while to make it fire like a projectile but failed miserably. Then i tried making an .xml plugin that I tried in insolence and ADI 2.0. The plugin put all the things that you can change in projectiles (initial and final projectile speed etc.) into the vehi tag. So now along with options to boost, fly etc. with a vehi tag I also have the ability to change its projectile speed etc. This seemed like a great idea but when i messed around with the properties for the projectile the gun still just plopped out warthogs. The only noticable change was that the warthog dissapeared when you werent looking directly at it.

Edit- Btw I got this idea from the bipd plugin with ADI 2 where the bipd has different flight options and you can make the masterchief/elite fly in multiplayer -the plugin worked

Can anyone give me any insight on what I might do to make it fire warthogs/any other vehi like a normal projectile?