This achievement is obtained after surviving the first fifty days without firing the hunting rifle or flare gun in a single Survival mode game. It is most easily done on Pilgrim. It is highly recommended to utilize the snare, survival bow and other craftables to their fullest extent in order to maximize chances of reaching fifty days survived.
This achievement must be attempted on the first fifty days of the play through. If the player fires the rifle or flare gun within the first fifty days of surviving it will nullify the achievement for that entire play through.
This achievement cannot be earned on Interloper since the rifle does not spawn.