[Jiver]

US_Grant,

If you are using UI 1.1 the sound files for the .50 cal should be the folllowing:

Preset: weapon.MGunBrowning50s.prs
Inside sample: MG_Browning50.wav
Outside sample: MG_Browning50x.wav

Do you have these files in your "files\samples" and "files\presets\sounds" folders?