In today’s new playlist update for Infinite Warfare, Infinity Ward has changed how Hardcore mode’s Ricochet will activate.
With this update, the ricochet only activates after a player has killed 2 teammates, meaning you have a 2 time grace period before it will start to reflect.
Hardcore friendly fire will only turn on reflect damage if you've killed two teammates. Two 'mulligans' then it's on you.
— David Mickner (@DavidMickner) January 13, 2017