I finally acquired the two shot Gauss Rifle from a Legendary Synth Trooper, after about 100hrs+ gameplay into it. My luck is 8. : r/fo4
UPDATE: I upgraded my Two Shot Gauss Rifle. It should go good with my two shot plasma rifle. Is the name good? Sorry for the quality. My perks include rifleman 4. :
Gauss Rifle image - Fallout mod for Mount & Blade - Mod DB
Fallout 76 Gauss Rifle Plan - Locations, Stats, and More - GameRevolution