From Valve Developer Community
Tip:Multiple reference meshes can be handled with a $bodygroup.
$body <name> "<reference mesh SMD>"
- A label for this $body to distinguish it from other reference meshes (if there are any).
- Path to and name of the 'reference' (sometimes 'model') SMD relative to the QC file's current directory. The
.smdextension is optional, but helps make the QC file easier to read.
$modelname "weapons/shell.mdl" $cdmaterials "models/weapons/" $body shell "shell_ref.smd" $sequence idle "shell_idle.smd"