Hey guys i was just woundering if you could tell me how to make the sky in the call of duty map maker???

This link should solve that question

One small addon on that tutorial. Do NOT use the hollow button, but make your sskybox out of 6 brushes on each side yourself. The Hollow button has been known to cause errors (as do the subtract and merge buttons next to it).

there is a simple tutorial located Here that will walk you through a skybox for cod

the difference between a box for cod and coduo is that you either have to texture the entire brush with the skytexture - or make it non-colliding - or the artillery in uo to work properly

Oh oh !!! :) Stryder, artillery in my map explodes off the ground, but it looks like it's about half way between the roof of the skybox and the terrain.. Any ideas why mate?
Grassy

see - i already answered the why...now it is up to you to fix it

I assumed you meant the artillery would hit the top brush of the skybox... ???

Grassy

sortof...for whatever reason when gmi coded the artillery strike, they used a set z value to spawn the artillery, rather than figuring out where the map started and ended (boundaries) through code

it seems that unless you make your skybox textured completely with a sky texture, or make it non colliding, it somehow distorts where the artllery spawns, and screws up the z value of where the ground is for the explosion effect