Grenade Launcher

A Grenade Launcher is a device that shoots a grenade. These can be standalone launchers, such as the Thumper or China Lake, or attachments, such as the M203. Grenade Launchers appear in several forms throughout the Call of Duty series.

Overview
The grenade shell has a safe arming distance of five to six meters and will not detonate unless it has traveled this distance before hitting a surface. Thus, shooting at nearby walls, ground or ceiling will simply cause the shell to bounce harmlessly away. This makes using a grenade launcher at close range very difficult. However, the shell will kill if it directly hits another player, and in turn the direct impact killfeed icon will be displayed. It is possible to even score a direct impact kill on multiple enemies with a single shell, though this is very rare.

In some games, the grenade launcher has restricted damage at the beginning of each round. This was likely done to make spawn-killing harder.

Call of Duty 4: Modern Warfare

 * GP-25 (Underbarrel, AK-47 only)
 * M203 (Underbarrel)
 * Mk 19 (Mounted)

Call of Duty: Modern Warfare 2

 * MK19 (seen in S.S.D.D. but never used)
 * M203 (Underbarrel)
 * GP-25 (Underbarrel, AK-47 only)
 * Thumper

Call of Duty: Black Ops

 * M203 (Underbarrel)
 * GP-25 (Underbarrel, AK47 and Galil only)
 * Tishina (Underbarrel, AK74u only)
 * China Lake

Call of Duty: Black Ops DS

 * M203 (Underbarrel)
 * M79

Call of Duty: Modern Warfare 3

 * M320 (Underbarrel on most weapons)
 * M203 (Underbarrel, M4A1 and M16A4 only)
 * GP-25 (Underbarrel, AK-47 only)
 * M320 GLM (Stand-alone variant)
 * XM25
 * Sentry Grenade Launcher (Survival Mode only)

Call of Duty: Black Ops II

 * M320 (Underbarrel on most weapons)
 * M203 (Underbarrel, FAL and Colt M16A1 only)
 * GP-25 (Underbarrel, on the AK47, Galil and AN-94)
 * War Machine
 * MM1 Grenade Launcher

Call of Duty: Ghosts

 * FN EGLM (Underbarrel)
 * Kastet
 * MK32

General

 * All grenades fired by grenade launchers are modeled the same (in the Modern Warfare series). This can be observed by looking at grenades that did not explode.
 * In Call of Duty: Modern Warfare 2 and Call of Duty: Modern Warfare 3, the player can complete a challenge called "Ouch" by killing someone with the grenade's direct impact. This will result in the title "Noob Tuber", a reference to the aforementioned derogative against players who use this attachment.
 * It is possible to get a headshot with a grenade from a grenade launcher. This is denoted if the grenade strikes an enemy directly and then explodes. This is the only way to instantly kill a Juggernaut in Spec Ops.
 * Any kill with the Grenade Launcher counts to the gun's total kills. The same goes for the Masterkey, Shotgun, Flamethrower and the Tactical Knife.
 * A kill with the M203 and GP-25 counts as a hip fire kill.
 * In the Modern Warfare series, the Create-a-Class icon is of a M203 (except for the AK-47 in Modern Warfare 2), where as in Call of Duty: Black Ops, the icon is of a GP-25.
 * The Grenade Launcher attachment is listed as a secondary weapon on the Call of Duty ELITE Create-a-Class menu.
 * In the Zombies mode of Black Ops, there is no minimum distance that the grenade must travel to explode; this can lead to shell shock if used at close range. In Black Ops II however, there is a minimum distance.

Call of Duty 4: Modern Warfare

 * In the extended mission of "F.N.G.", it was stated that the grenade launcher cancels out when fired too close for "safety" purposes.
 * If the 'Infinite Ammo' cheat is activated in the campaign, the grenade launcher becomes fully automatic. The M203 on the M4A1 will fire at 200 RPM, and the GP-25 at 120 RPM, whereas the M203 on the M16A4 will fire significantly faster at 600 RPM.
 * There were originally three more grenade launchers: AG36 (G36C), HK79 (G3) and FN EGLM. The names can be found in localized strings.

Call of Duty: Modern Warfare 2

 * When using Scavenger, the grenade has to be loaded to pick up another grenade. There are two slots for the grenade launcher: one that is loaded and one that is in reserve.
 * The Create-a-Class picture lacks a trigger-guard.
 * On the FAL, the grenade launcher is misspelled as "Grenade Laucher".
 * There is a odd camouflage changing glitch that occurs when the player has two of the same weapons equipped with a grenade launcher, different optics and different camos. If the player switches to their grenade launcher, the camo will alternate between the two camouflages. This works with the Shotgun attachment, but both guns must have the same underbarrel.

Call of Duty: Black Ops

 * In the first 15 seconds of a match, any grenades from a grenade launcher will never explode. This was done to prevent using the grenade launcher to kill the enemy team quickly upon spawning, as they are naturally stacked up.
 * In the campaign, in third-person, non-playable characters hold their weapon as if it does not have an Grenade Launcher, but in multiplayer and Zombies, they do.

Call of Duty: Modern Warfare 3

 * Using the underbarrel grenade launcher replaces the regular ammo counter with its own, unlike in previous games.
 * The damage output seems to have been lowered for balancing purposes and Recon tags. Kills by the grenade launcher now usually occur by direct impact, close proximity detonation, or killing an enemy with low health.
 * Oddly, there is no killfeed icon for the Grenade Launcher. Kills with it show up as the gun it is attached to. The same applies to the shotgun attachment.

Call of Duty: Black Ops II

 * When playing a 1980's campaign mission, using the underbarrel grenade launcher doesn't replace the regular ammo count with its own, but it does in the 2025's missions, as well as in multiplayer and Zombies.
 * There is a small delay between firing the grenade launcher and it actually firing in-game. The grenade launcher explosive delay time can differ between certain game modes.
 * When using Fast Mag, the Grenade Launcher will reload faster.

Call of Duty: Ghosts

 * When killing an enemy with the grenade launcher by the grenade hitting them, the "Noob Tuber" emblem is unlocked. This is a reference as many people refer the grenade launcher as the "Noob Tube".