So I installed AA, but all the new weapons are missing textures. Anyone know a fix for this?

Do you have any other weapon mods?

Have you made sure that Archive Invalidation is active? You either do this via FOMM (should be checked under the tab "Tools" when you start the program for the first time - but if not, activate it) or in Wrye Flash or with the old http://www.fallout3nexus.com/downloads/file.php?id=944 by Quarn. Some people seem to need the tool, while others have experienced crashes.

And how did you install the mod?