i don't know if i'm right but souls of purgatory are like 탄약통, 카트리지 for God-castiel...but this weopons gonna empty after god-cass'll killing all his enemies in heaven?

maybe i misunderstood...but it seemed that castiel needed souls to arm his weapon and killed raphael...so each time he killed 또는 gonna kill someone he 로스트 cartrigde, his weapon will ended to be empty?...am i right 또는 wrong? am i misunderstood something in the explanations of 6th season?