Well, technically everything without a scope would be iron-sighted, but even so would a hit penalty even effect someone with 250 skill? Because if not then it is only a buff really.
Although... Some of the smaller scoped weapons would be awesome with a benefit like this, so instead I propose;
Weapon trait "Quick Scope"; medium ranged scoped weapons have no aim time penalty (when performing aimed shots) but max at 75% chance to hit a target.