Bonk Melee SFX

Find FNV in your Steam directory and look for the Data folder
i.e C:\Program Files (x86)\Steam\steamapps\common\Fallout New Vegas\Data

Replace Fallout - Sound.bsa with the downloaded file

PSA!!
Make sure to make a copy of the original BSA file so you can revert back if you wanna go back to default sounds or in case you have any issues