The NCR's Service Rifle from Fallout: New Vegas replaces the SCAR (Desert Rifle) with this addon, complete with the game's native firing sound.
The first weapon you picked up thinking 'Wow, this does pretty weak damage for a rifle.' Have you ever had a certain type of problem out in the wasteland that needed fixing? Like a problem with hordes of misguided teenagers in football gear throwing spears at you? Or a problem with fire-breathing geckos burning down your tent as you try to get your 4 hours of shift-assigned sleep? Well chances are you'll find yourself right at home when you pick up this good 'ol boy.
'Patrolling the Mojave almost makes you wish for a nuclear winter.' - every single NCR soldier