Weapon Mods

Weapon Mods are applied to assault rifles, shotguns, sniper rifles, submachine guns, and heavy pistols to augment them in Mass Effect 3. Available mods include high-caliber barrels, scopes, and bayonet attachments, among others. Only two mods can be applied to a weapon at a time, and the same mod cannot be applied twice to a single weapon.

Once a weapon mod is found, it may be applied to any and all of the weapons of the applicable type at a weapon bench. Finding another instance of a mod the player already possesses will upgrade that mod to the next level. Likewise, shops will always carry mods one level above those the player currently has.

Assault Rifle Stability Damper
Distributes recoil with sliding system of counterweights compatible with kinetic coil generators. Reduces weapon kickback.

Changes the color of the weapon's handle and stock depending on level of mod.

Assault Rifle Magazine Upgrade
Increases magazine capacity, allowing more shots before reload.

Changes the color of the weapon's body depending on weapon and level of mod.

Assault Rifle Piercing Mod
Capacitor boosts kinetic coil generators, increasing shot penetration.

Changes the color of the weapon's lights depending on level of mod.

Assault Rifle Extended Barrel
Lengthens barrel, creating greater bullet velocity and impact.

Places a visible barrel extension on the weapon with a different appearance depending on the level of mod.

Cannot be equipped with High-Velocity Barrel.

Assault Rifle Precision Scope
Simple 4x optical scope to enhance stability while zoomed. Increases accuracy while moving and taking damage.

Places a visible scope atop the weapon with a different appearance depending on the level of mod.

Assault Rifle Omni-Blade
Attach an omni-blade to the weapon for increased melee damage.

Places a visible omni-bayonet on the weapon.

Requires Mass Effect 3: Leviathan in single-player and Mass Effect 3: Earth in multiplayer.

Assault Rifle Thermal Scope
Reveal enemies through walls and smoke with a 4x optical scope and enhance stability and accuracy while zoomed.

Places a visible thermal scope on the weapon.

Added to multiplayer on October 9, 2012.

Assault Rifle High-Velocity Barrel
Superior kinetic coils increase shot penetration.

Places a visible barrel extension on the weapon.

Added to multiplayer on October 9, 2012.

Pistol Melee Stunner
Small attachment to muzzle, causing massive damage to meleed targets.

Adds a visible stunner beneath the barrel. Also changes the color of the weapon's handle depending on level of mod. Adds electrical visual and sound effects to melee attacks that hit enemy with the gun.

Pistol Piercing Mod
Capacitor boosts kinetic coil generators, increasing shot penetration.

Changes the color of the weapon's lights depending on level of mod.

Pistol Magazine Upgrade
Increases magazine capacity, allowing more shots before reload.

Changes the color of the weapon's body depending on weapon and level of mod.

Cannot be equipped with Ultralight Pistol Materials.

Pistol High Caliber Barrel
Allows wider projectiles, causing more trauma on impact. Ballistically optimized to maintain penetrative power.

Places a visible barrel extension on the weapon.

Cannot be equipped with Heavy Barrel. Cannot be equipped with Cranial Trauma System.

Pistol Scope
Simple 2x optical scope enhances stability while zoomed. Increases accuracy while moving and taking damage.

Places a visible scope atop the weapon.

Pistol Cranial Trauma System
Increase headshot lethality by balancing barrel calibration so that ammunition pierces bone and explodes in soft tissue.

Places a visible barrel extension on the weapon.

Requires Mass Effect 3: Leviathan in single-player and Mass Effect 3: Earth in multiplayer. Cannot be equipped with High Caliber Barrel. Cannot be equipped with Heavy Barrel.

Pistol Ultralight Materials
Superior lightweight alloys replace weapon parts, making the weapon less obtrusive and easier to handle.

Changes the color of the weapon's body depending on weapon and level of mod.

Requires Mass Effect 3: Leviathan in single-player and Mass Effect 3: Earth in multiplayer. Cannot be equipped with Pistol Magazine Upgrade.

Pistol Heavy Barrel
A pistol barrel that produces and withstands extreme kinetic and thermal energy.

Places a visible barrel extension on the weapon.

Added to multiplayer on October 9, 2012. Cannot be equipped with High Caliber Barrel. Cannot be equipped with Cranial Trauma System.

Shotgun Spare Thermal Clip
Adds sockets to raise thermal clip capacity, increasing number of spare shots.

Changes the color of the weapon's handle and stock depending on level of mod.

Shotgun Shredder Mod
Capacitor boosts kinetic coil generators, increasing shot penetration.

Changes the color of the weapon's lights depending on level of mod.

Shotgun Blade Attachment
Tungsten-carbide bayonet with recessed edge for increased melee damage.

Places a visible bayonet underneath the barrel. Adds slashing sound to melee attacks that hit with the gun.

Shotgun High Caliber Barrel
Allows wider projectiles, causing more trauma on impact. Ballistically optimized to retain penetrative power.

Places a visible barrel extension on the weapon.

Cannot be equipped with High-Velocity Barrel.

Shotgun Smart Choke
Servo motors hooked up to adjustable system tighten or loosen pellet spread for maximum accuracy.

Changes the color of the weapon's body depending on weapon and level of mod.

Shotgun Omni-Blade
Attach an omni-blade to the weapon for increased melee damage.

Places a visible omni-blade on the weapon.

Added to multiplayer on October 9, 2012.

Shotgun High-Velocity Barrel
Superior kinetic coils increase shot penetration.

Places a visible barrel extension on the weapon.

Added to multiplayer on October 9, 2012.

Sniper Rifle Concentration Mod
Biometric sensors and auto-targeting software adjust to the user's pulse and breath rate, assisting aim.

Changes the color of the weapon's lights depending on level of mod.

Single-player Only Stacks with Adrenaline Rush and Operational Mastery.

Sniper Rifle Spare Thermal Clip
Adds sockets to increase thermal clip capacity, increasing number of spare shots.

Changes the color of the weapon's handle and stock depending on level of mod.

Sniper Rifle Extended Barrel
Lengthens barrel, creating greater bullet velocity and impact.

Places a visible barrel extension on the weapon.

Cannot be equipped with High-Velocity Barrel.

Sniper Rifle Piercing Mod
Capacitor boosts kinetic coil generators, increasing shot penetration.

Changes the color of the weapon's body depending on weapon and level of mod.

Sniper Rifle Enhanced Scope
Stability-enhancing scope increases accuracy while moving and taking damage. Highlights targets through smoke.

Adds visible extension to scope.

Sniper Rifle High-Velocity Barrel
Superior kinetic coils increase shot penetration.

Places a visible barrel extension on the weapon.

Added to multiplayer on October 9, 2012.

Sniper Rifle Thermal Scope
Reveal enemies through walls and smoke with a 4x optical scope and enhance stability and accuracy while zoomed.

Places a visible barrel extension on the weapon.

Added to multiplayer on October 9, 2012.

SMG Ultralight Materials
Superior lightweight alloys replace weapon parts, making the weapon less obtrusive and easier to handle.

Changes the color of the weapon's body depending on weapon and level of mod.

Cannot be equipped with Recoil System.

SMG Magazine Upgrade
Increases magazine capacity, allowing more shots before reload.

Changes the color of the weapon's handle and stock depending on level of mod.

SMG High Caliber Barrel
Allows wider projectiles, causing more trauma on impact. Ballistically optimized to retain penetrative power.

Places a visible barrel extension on the weapon.

Cannot be equipped with High-Velocity Barrel.

SMG Heat Sink
Increases heat conductivity of thermal clip receiver. Negates heat generated by some shots.

Changes the color of the weapon's lights depending on level of mod.

SMG Scope
Simple 2x optical scope enchances stability while zoomed. Increases accuracy while moving and taking damage.

Places a visible scope atop the weapon.

SMG High-Velocity Barrel
Superior kinetic coils increase shot penetration.

Places a visible barrel extension on the weapon.

Requires Mass Effect 3: Leviathan in single-player and Mass Effect 3: Earth in multiplayer. Cannot be equipped with High Caliber Barrel.

SMG Recoil System
Increase weapon mass for a split second per shot by using expert timing-VI to reduce weapon kick and improve aim

Changes the color of the weapon's body depending on weapon and level of mod.

Requires Mass Effect 3: Leviathan in single-player and Mass Effect 3: Earth in multiplayer. Cannot be equipped with Ultralight Materials.

Player Notes

 * The damage bonus provided by certain mods (most notably High Caliber Barrel) stacks additively with that provided by skills such as class or racial passives and Tactical Cloak. For example, an Infiltrator Shepard who took every weapon damage upgrade for Operational Mastery and Tactical Cloak and put a High Caliber V mod on his weapon will deal 100% + 10% + 90% + 25% = 225% of base damage.
 * The Piercing and Shredder mods increase damage versus armored targets by ignoring part of damage reduction that every bullet striking an armored target suffers. A good approximation is to treat the result as a fixed (independent of weapon damage) damage bonus on every bullet (and every shotgun pellet) striking an armored target. As a result, rapid-fire weapons receive a much greater benefit from these mods than slow-firing ones.
 * Magazine Upgrade mods do not change the amount of spare ammo a weapon holds, however, the increased capacity is not deducted from the spare ammo pool either - if a weapon normally holds 100 rounds and 500 in reserve, applying a Magazine Upgrade V will change that to 180 rounds and 500 in reserve, for a total of 680.
 * Mods that increase a character's melee damage apply that bonus even if the character's melee attack does not actually strike with the weapon, for example drell and krogan light melee, or geth and asari heavy melee, even though these attacks will not trigger the sound and/or hit effects associated with the mod.
 * Optical scopes generally increase the effectiveness at range with any weapon, though caution should be advised since it also decreases your peripheral vision slightly. This can cause enemies to flank you more easily.
 * Spare ammunition mods tend to be more useful on weapons that have very little ammunition on reserve, such as the Reegar Carbine, or the M-98 Widow. While it is also helpful with weapons with a much larger reserve such as the M-13 Raptor, its effects are usually unnecessary unless playing against enemies on harder difficulties.