The DKS has the Accurate, so that's +30 hit chance, with 250 skill you will have 95% hit chance at 81 hex with unaimed shots. PE has no impact on that.
With 10 PE a eye-aimed shot will have 95% at 75 hex, with sharpshooter 77.
With 5 PE a eye-aimed shot will have 95% at 69 hex, with sharpshooter 71.
The flamer even with 250 skill and 20PE (because PE will have no impact on the hit chance!) will have 95% at 7 hex.