Characteristic Bonuses and Modifiers

By Shadowthorne, in Dark Heresy Rules Questions

Do modifiers on attacks ( Aim, Std attack, all out attack) increase your weapon skill bonus for the purposes of that attack? such as for effects that cap based on ur weapon skill bonus.

I.e a character with weapon skill 41 makes a lightning attack, after a full action aim(+20). He rolls a 10(4 degrees + initial degree for passing, for a total of 5). Lightning attacks additional attacks cap at the characters WSB, so does he score 4 attacks, or does he get 5 due to the +20 from Aim?

I guess it's not actual, but can be useful for someone later on.

Weapon skill is a characteristic, so we use the rules under characteristic bonuses, what says:
" In addition to its numerical value, each characteristic has a
characteristic bonus, a number equal to the “tens” digit of that
characteristic. For example, a character with a Strength of 42
would have a Strength bonus of 4.
"
-DH 2E Core rulebook pg. 21. topright corner

When you get a bonus for aim, or lightning attack, you get that bonus for that test. So your characteristic stays the same as well as your characteristic bonus.
In your example, the character would cap at 4 attack.

Another example is wearing armour. If a character wears a Chainmail Suit, it caps their agility at 35. So if the character would have 40 agility so a 4 Agility Bonus without the Chainmail Suit , his/her agility and agility bonus would be 35 and 3 respectively wearing the armour. This is because the modification applies to the characteristic, and not the test made using the characteristic. Wearing the Chainmail Suit, a Routine(+20) agility test would succeed on a roll of 55 or lower, but the character's agility bonus still would be 3.