In Call of Duty: Modern Warfare 3 (MW3), weapon customization plays a crucial role in how players approach every combat scenario. One of the most impactful attachments available in the Gunsmith system is the underbarrel lethal attachment. These additions turn your primary weapon into a versatile tool capable of delivering explosive or high-impact damage, often giving players the upper hand in both close-quarters and mid-range encounters. Understanding how underbarrel lethal attachments work, which ones are the most effective, and when to use them can greatly enhance your loadout strategy in multiplayer and Warzone modes.
What Is an Underbarrel Lethal Attachment?
An underbarrel lethal attachment in MW3 refers to a secondary device mounted underneath the barrel of a primary weapon, usually assault rifles or battle rifles. These attachments provide a secondary firing option that deals lethal damage, often involving explosives or high-powered projectiles. They’re different from regular attachments because they function as standalone tools that expand your tactical options without replacing your main firing method.
Key Characteristics
- Mounted under the main barrel of the weapon
- Fires independently of the main gun
- Typically includes explosive rounds or high-impact slugs
- Best suited for breaching, crowd control, or suppressive play
Popular Types of Underbarrel Lethal Attachments
MW3 offers a selection of underbarrel lethal attachments, each with its own unique function and use case. Choosing the right one depends on your playstyle, map selection, and intended combat range.
1. Underbarrel Grenade Launcher (UBGL)
Arguably the most iconic of all underbarrel lethals, the grenade launcher delivers explosive payloads at medium ranges. It’s effective for clearing out rooms, punishing campers, or breaking defensive lines. However, it usually comes with limited ammo often just one or two shots so precision and timing are key.
2. Shotgun Underbarrel
This attachment acts as a mini shotgun, useful in close-quarters situations. While it doesn’t match the power of a full-size shotgun, it adds serious stopping power to any rifle. It’s especially deadly in tight hallways or buildings where enemies are likely to ambush you.
3. Thermobaric Launcher
Designed to cause area-of-effect damage, the thermobaric launcher can incapacitate enemies behind cover or inside buildings. Its splash radius makes it ideal for dealing with groups of enemies or flushing out players using deployables like Trophy Systems or Riot Shields.
4. Gas or Smoke Launchers
Though technically not always lethal, some underbarrel launchers deploy gas or smoke rounds. These can be used tactically to disorient or force enemies out of cover. While not directly fatal, they can complement lethal gameplay by weakening opponents before engagement.
Best Loadouts Featuring Underbarrel Lethal Attachments
If you’re considering integrating underbarrel lethals into your MW3 class setup, it’s important to build around them intelligently. Below are a few examples of optimized loadouts that take full advantage of underbarrel lethality.
Assault Loadout with Grenade Launcher
- Primary: M4 or TAQ-56 with Grenade Launcher
- Secondary: Combat Knife (for speed)
- Perks: Scavenger, Quick Fix, Fast Hands
- Tactical: Flash Grenade
- Lethal: Semtex or Frag
- Field Upgrade: Munitions Box (to restock launcher ammo)
Close-Quarter Combat Loadout with Underbarrel Shotgun
- Primary: Kastov-74U or Chimera with Underbarrel Shotgun
- Secondary: X13 Auto
- Perks: Battle Hardened, Tracker, Ghost
- Tactical: Stun Grenade
- Lethal: Drill Charge
- Field Upgrade: Dead Silence
When to Use Underbarrel Lethal Attachments
Underbarrel lethal attachments are situational tools. While they can be extremely effective in the right hands, they also require situational awareness and map knowledge. Here are key moments when they shine:
- Breaching Rooms: Perfect for clearing tight interiors or objective areas
- Clearing Head Glitches: Launchers help dislodge entrenched enemies
- Suppressing Groups: Thermobaric and grenade options can damage or kill clustered foes
- Panic Situations: An underbarrel shotgun can turn the tide when enemies rush your position
Drawbacks to Consider
Despite their power, underbarrel lethals come with some limitations. Knowing these drawbacks will help you decide if the trade-off is worth it for your loadout:
- Limited Ammo: You usually get only one or two shots per life
- Slower ADS: Some attachments slightly affect aim-down-sight speed
- Increased Weight: Can reduce sprint-to-fire or movement speed
- No Attachment Stacking: Using a lethal underbarrel may prevent other underbarrel options like foregrips
Tips for Mastering Underbarrel Lethals
To make the most out of these attachments, players should practice proper aiming and timing. The projectile arcs and travel time can be tricky, especially for explosive rounds. Use the following tips to increase effectiveness:
- Always account for arc and drop when using grenade-type launchers
- Pre-aim doorways or high-traffic zones for surprise kills
- Use Munitions Box or Scavenger to maintain ammo levels
- Combine with tactical equipment like flashbangs for easier cleanup
Game Modes Where Underbarrel Lethals Excel
Some MW3 game modes benefit more from lethal underbarrel use than others. While they can be used in nearly all settings, the following modes stand out:
- Hardpoint: Perfect for breaking into or defending zones
- Domination: Use them to control objectives
- Search and Destroy: Great for breaching bomb sites and eliminating campers
- Ground War: Effective in larger-scale battles where enemies cluster together
Underbarrel lethal attachments in Modern Warfare 3 offer a powerful addition to any operator’s arsenal. Whether you prefer to explode into action with a grenade launcher or dominate close encounters with a compact shotgun, these attachments give you more options without sacrificing your primary weapon’s utility. While they come with limitations like slower handling or limited ammo, mastering them can turn you into a more versatile and dangerous player. If used wisely, an underbarrel lethal attachment can mean the difference between a tight loss and a game-winning play.