Russian Roulette is a gear perk that speeds up your reload after a headshot kill. It suits precise shooters who line up a headshot and want to be ready for the next target quickly.
Kill an enemy with a headshot and your next reload goes faster. It helps most with weapons that reload slowly, like sniper rifles.
Wear one of the listed watches or gloves. Gear perks are fixed to the piece of clothing that carries them, so you get this one by wearing that piece, not by unlocking it in a menu.
Thrifty Shooter refunds the round on headshot kills, so the two together keep a precise build running.