From Ultramarine Supplement
FAQ
Q. If I select a weapon with more than one profile for the Master-crafted Weapon Special Issue Wargear (e.g. a plasma pistol), does the increased Damage characteristic apply to all profiles of that weapon, or must I select which profile of that weapon is improved? A: Add 1 to the Damage characteristic of all profiles of that weapon. Note that weapons with similar names but listed separately in the weapons table, such as boltstorm gauntlet (melee) and boltstorm gauntlet (shooting), are considered separate weapons, rather than the same weapon with different profiles.
So whilst from Ultramarine Supplement the precedent seems clear