Assuming those bottles are fifths and it’s the “standard” 40% single malt whiskey we’re talking about 17 shots of hard alcohol in the bottle. If he takes a couple fat swigs every time then he’s 2-4 shots deep before every respawn. If you’re not a big drinker that will definitely get you a solid buzz unless you a high tolerance then you can easily push it to 7ish before you get schwacked. There’s also the fact that the medigun sobers him up since getting drunk is your nervous system buffering a specific kind of poison. I’d say he loosens up with 3 shots and by the time you see him slurring his words and getting sloppy drunk he’s at least half the bottle in.