The Sentry Grenade Launcher is a piece of equipment featured in Call of Duty: Modern Warfare 3's Survival Mode that is unlocked at Level 31 and costs $4000. The Sentry Grenade Launcher is a movable Mk 19 automatic grenade launcher, making it devastatingly more powerful compared to the normal Sentry Gun. As a downside, it is shorter, making it useless when stationed at a window and a hazard to itself and everything around it when it fires. The blast shield can provide cover from small to medium sized infantry. Like its counterpart, Juggernauts and Little Birds will automatically target Sentry Guns and Sentry Grenade Launchers if they haven't acquired the player first. It's advisable that the player leads Juggernauts away from Sentry Guns/Sentry Grenade Launchers and keep them under cover from Little Birds in order to extend their lifespan.
It is ineffective against enemy air support due to the grenade's slow travel time but does significant damage if it registers a hit. The sentry's slow rate of fire makes it difficult for it to hit dogs strapped with C4 and mobile armored infantry, but because it can target enemies and fire faster than the Sentry Gun and deals more powerful grenades, it can be a great "partner" that can defend from corners and choke points effectively. However, due to the large blast radius, if placed in small/tight spaces, it often will blow itself up in a few shots, rendering it a waste of money unless placed correctly.
Large groups of enemies are extremely vulnerable due to the sentry's high blast radius, although the large blast radius may lead to friendly-fire incidents on Delta Squads, Riot Shield Squads, and on fellow players. Just like its counterpart, its AI will shoot at any enemy within its range, regardless of who or what stands between it and its intended target.