Fallout 4 weapons

Unlike previous installments, in Fallout 4, weapons fall under three classifications: Normal, legendary, and unique. Normal weapons have no special statistics on them whatsoever. Legendary weapons come with random bonuses applied to them, and are only dropped by legendary enemies. Unique weapons are weapons that are already named and will always retain the same special bonus. Uniques are typically either bought from merchants or are quest rewards. Normal and legendary weapons will change their name when mods are applied, unique weapons will not.

All stats are given with standard weapon modifications.

Other
All these weapons count as non automatic weapons and thus work with either Gunslinger, Rifleman, or Sniper respectively, except the Cryolator, which is counted as a heavy gun and thus works with Heavy Gunner.

Radiation weapons
These weapons produce radiation damage, including both direct damage from explosions and damage over time from exposure and poisoning. There is some variance in how damage is dealt within this class of weapon; please consult each weapon's page for specific details. Also, the radiation page explains the unique ways that this kind of damage is handled by the game. These are affected by the perk Nuclear Physicist in terms of radiation damage.

Poison weapons
Poison weapons utilize the poison damage type to deal ongoing damage to targets.

Explosives
Explosives have a maximum range of 93. They seem to hit an invisible wall at their maximum range. Explosives benefit from the Bloody Mess, Demolition Expert and SCAV! - Cautionary Crafts perks, but only for their "primary" damage effects (which always includes the Explosive legendary prefix); this is why the Pulse grenade and Pulse mine are not affected by any of the 3.

Melee weapons
Damage found in the table is base damage, every point of Strength adds 10% to it. Several perks can further increase the damage displayed for a melee weapon.

Bladed
Bladed weapons can dismember limbs of humanoid opponents, permanently damaging the limb and disarming the target. Like all melee weapons, bladed weapons benefit from Big Leagues and Strength.

Blunt
Blunt weapons tend to stagger opponents more frequently than bladed weapons. Like all melee weapons, blunt weapons benefit from Big Leagues and Strength.

Fist weapons
Fist weapons benefit from the Iron Fist perk as well as from Strength. Note that fist weapons cannot be used while wearing power armor.

Renaming weapons
In Fallout 4, the player character is able to rename any weapon, including unique weapons, at any weapons workbench. Renaming weapons does not affect any weapon stats. This primarily adds a level of personalizing to weapons and can help avoid accidentally disassembling a favored weapon.
 * Special and accented characters (i.e. alt-codes) can be used when renaming a weapon. Bold and italic can also be used.

Mods
Weapons may be modified in Fallout 4. Each weapon has modification 'slots' (e.g. barrel, grip, magazine, sights) that may be modified with increasingly powerful or useful mods by the player character based on their perks. However, the player character may salvage useful mods that are not yet available via the player character's perk level by simply modifying any weapon that already has the mod of interest. By replacing the mod of interest with any available mod the original mod goes into inventory and may then be used to alter the player character's chosen weapon without regard for their perk level. Unique weapons do not offer this capability; their special mods are 'reserved' and since they are unique, no other examples are available to be salvaged.

Bugs

 * Sometimes, when starting the game, gunfire cannot be heard on certain weapons. This can be fixed by re-starting the game or re-loading to a previous save file.
 * Sometimes, when using a night vision scope, the night vision effect will stick around after going out of the scope.

In Fallout 4

 * Fallout 4 ammunition
 * Fallout 4 weapon mods
 * Fallout 4 unique weapons
 * Legendary weapons

In the rest of the Fallout series

 * Fallout weapons
 * Fallout 2 weapons
 * Fallout Tactics weapons
 * Fallout 3 weapons
 * Fallout: New Vegas weapons