It's been a pleasure :)

As for the boomer: Are we talking about the headcrab shells? In any case, anything with rockets sounds a bit... difficult if you want to do it right. I don't think I'll touch that subject in the foreseeable future. Maybe when I'm in the mood to do something for GMod again I'll pick it up though - but no promises.

Yes the headcrab shelled ones. Its ok but thanks anyways :)

Never mind I found it. Sorry for the inconvenionce.

Maybe gun can be used by npc?

Theres a tool for it. Its called half life 2 tools. U can now left click to spawn in a artillary shell.

Maybe make the guns accuracy line up with the crosshair? There is a hl2rp plugin for this and it is perfectly accurate so it is possible

I've had to choose between having the crosshair line up with where the gun would shoot, and just align where the gun would shoot up with the crosshair. The latter is much easier to implement, but looks wrong because the projectiles would leave the gun at odd angles. The first is annoying as hell to do. When I've made this... which is by now over five years ago I guess, I've spent a lot of time trying to get the crosshair right, but ultimately failed.

It involves lots of maths and I couldn't be arsed to deal with it. Still can't.