@Mr something ok, lets check few things :
• If your retexture mod has an esp or esm, place it late in your load order.
• Make sure you do not have any mod that overrides your retextures, disable (untick your mods from launcher) progressively and test IG, untill you find the culprit.
• IF it didn't work, rename temporarilly your
data/textures folder to ensure eventual loose files are not overriding the ones of the *.bsa file used by the retexture mod. If it worked, delete these loose files, probably in
data/textures/weapons...
• Selective job : you may also use
FO3edit and check the mod (s) that overwrites your weapons retextures, particularly the first person model. Simply delete every entry suspected to overwrite. Select the mod and expand it in the left column, then expand the weapon sub-section, find all the needed references, assault rifle, chinese rifle, etc.. select them one by one in the left column and right-click and remove, as shown here
Ctrl + s to save, then Alt + F4 to quit, Good hunting