Actually the Cubemaps are quite an advanced area. Sure it's a hell of a drag to make them for general use, but you can get some truly spectacular reflections with Sources Cubemap's. (Seeeing as you can change the size too.
)
Anyways, find that material name, open TF2 Materials.gcf (steam/steamapps) and browse to it.
(Might be like blend/groundgravel01 or something)
Open the .vmt, and you should get something like this:
Code:
"WorldVertexTransition"
{
"" "nature/dirtwall001a"
"" "nature/grassfloor002a"
}
(The Nature/blah was stolen from Hl2's)
Change your second texture ($BaseTexture2) to a new texture.
Do NOT use a blend for the second one, it causes problems. So use like dirt/dirt01
Save your new VMT to USERNAME/Team Fortress 2/tf2/materials/WHEREVERYOUGOTITINTHEGCF.
Any more questions and I can fix that. Or post the texture name, and when I get home i'll fix it up for you.
More on cubemaps is: They are placed how they are for the lights. Basically one places one in the center of a "Light" area, and in the center of your shadows. Thisway when you build cubemaps it reads the dark faces around it, and makes your gun reflect DARK and not LIGHT.