Rifleman (Fallout 4)

Rifleman is a perk in Fallout 4 and Fallout 76. This perk affects both energy and ballistic weapons, but only reduces a target's ballistic damage resistance, not energy or radiation resistance.

Effects
Rank 4 gives a 6% chance to cripple the limb you hit. Rank 5 increases this to an 8% chance. In addition, if Nuka-world is installed, Rifleman now becomes a crafting perk, mainly required for the non-automatic variant of the handmade rifle.

Affected weapons
Whether or not eligible weapons receives a bonus from this perk depends on the mods attached. A non-automatic receiver must be in place. For weapons that are pistols/revolvers in their basic state, a full size shoulder supported stock/grip must be in place (the automatic name generation must label the weapon a rifle, shotgun or scattergun, and not a pistol).

Damage total
Since the actual damage dealt is affected by damage-to-armor ratio, we can analyze how both damage increase and armor reduction affects real damage.

The following calculations assume no criticals (which scale differently than how sneak attack multiplier scales):

For ballistic non-automatic rifles: $$DmgMulti=\Bigg(\Bigg[\frac{RiflemanDmgMulti}{RiflemanArmorMulti}\Bigg]^{.366}\Bigg)*RiflemanDmgMulti$$

For any other non-automatic rifle: $$DmgMulti=\Big(\Big[RiflemanDmgMulti\Big]^{.366}\Big)*RiflemanDmgMulti$$

These equations assume that the resultant damage-to-armor ratio doesn't exceed 6.45 (that the resulting damage of the weapon is at most 6.45 times the resulting armor value of the enemy).

Note: "X" represents the multiplier of this component.

Gallery
Fusilier Karabinier Эксперт по карабинам