The Familiar

If an Inquisitor has one or more Familiars in his retinue, he benefits from +1 Initiative. For each Familiar the Inquisitor has in his retinue, he may purchase one more psychic power than normally allowed. However, he may only use one of these powers per turn. When the Inquisitor is removed from play, any Familiars he may have had are also removed. If the Familiar is removed, the Inquisitor's psychic power is unaffected

Weapons like chainswords, rifle butts, combat blades, bayonets, etc., do not confer any particular bonus to the model using them. Remember that, in close combat, pistols count as normal close combat weapons and so the Strength and AP of the pistol are ignored.