How come when i install certain models they dont play the reloading etc sounds? What do i do to fix this? Its never happened to me befiore

That's up to the people who compiled the models. It's in the QC file that tells compilers how to pack the animations in to the MDL files, then tells HL when to play events associated with the animations [sounds, sprites, et cetera]. In the stickied posts above, you'll find information on decompiling MDL files. Once decompiled, if you selected the correct options within the decompiler [Kratisto's, which comes with Milkshape seems to be the most widely used--correct me if I'm wrong, though] you'll have the QC file. Open it with NotePad. Scroll down to the lines that mention the appropriate animations. There'll be mentions of number-coded events and, hopefully, paths to the sounds that should be playing during those animations. Perhaps they're editted to point to custom sounds, perhaps they're not there at all. You can decompile the default models and look at their QC's to see what files they point to. Be careful when changing the timing of the events, though, as they may not work with custom animations [clicks won't line up, for example].

sic thx... i thought it played the default sound.. by default no matter what. i never bothered to decompile a model

yeah a lot of models are compiled with reload sounds. ie; carbine_draw_clipout, carbine_draw_clipin, carbine_draw_slideback

although lately i have been noticing some models that use those sounds dont come with them, leaving a noiseless animation.

the model i just dled doent have sounds included..... and its noiseless :\ the devin kryss stg44

exactly the one i was referring to. i had to add my own mp44_shoot, mp44_draw_slideback, mp44_reload_clipin, and mp44_reload_clipout. contact me on AIM on Fetal Ichthyosis and I'll send you the sounds, or you could use whatever ones you'd like