Sentry Gun

From Team Fortress Wiki
Revision as of 04:49, 13 July 2012 by Moussekateer (Talk | contribs) (Undo edit by ISmile03 (Talk) (1087736) The quote is 'use a gun')

Jump to: navigation, search
The Engineer with a Level 3 Sentry
How am I going to stop some big mean mother hubbard from tearing me a structurally superfluous new behind? The answer: use a gun. And if that don't work... use more gun.
The Engineer on defensive measures.

The Sentry Gun, also known as the Sentry Mechanical Firing Device, Sentry, Turret, or simply abbreviated to SG, is a building that can be constructed by the Engineer using the PDA, the Engineer's build tool. The gun itself is a tripodal device constructed of metal, team-colored paint, and a laser sight (when used with the Wrangler).

The Sentry Gun functions as an automated turret which fires at the closest enemy within its range and line of sight. Dealing constant as well as consistent damage with noticable knockback and an immunity to critical hits, a Sentry Gun is the cornerstone of a successful defensive setup. On the other hand, they take a while to set up to full potential, and even a fully-stocked Sentry Gun can be destroyed with little trouble by a well-executed Übercharge or a Spy with his Sapper. Engineers must be on the lookout for such threats to ensure their Sentry Gun's survival.


The Sentry Gun costs 130 Metal to build, 200 Metal to upgrade to level two, and an additional 200 to upgrade to the third and final level totaling to 530 Metal. With each upgrade level, the Sentry Gun becomes more powerful, gaining machine guns, rockets, as well as more health. The firing range remains constant regardless of level. The Sentry Gun's ammo and health may be replenished with Metal by the Engineer hitting it with his Wrench. Each bullet reloaded costs 1 Metal and each rocket reloaded costs 2 Metal.

When placing a Sentry Gun, the limit of its range is represented by a 3D sphere of the team color with a radius of 1100 Hammer units. A Sentry Gun that is being constructed will have its health increase gradually until it reaches its maximum health upon completion. The Sentry Gun rotates 90 degrees to patrol the area, but is capable of rotating 360 degrees to lock on to a target. This takes a brief moment however, which may allow faster foes to slip past its range. The Sentry Gun can also be manually rotated to face a different direction before building commences. When the blueprint is shown, using the alternate fire button (default key: 'MOUSE2') will rotate the blueprints counter-clockwise by 90 degrees.

Sentry Guns will not fire upon enemy Spies that are cloaked or disguised. Sentry Guns will also not fire upon enemies in its range if there is a water surface between them or if the enemy is behind cover - this cover includes the Engineer's Dispenser. Sentry Guns are also unable to fire if an enemy Spy attaches an Sapper to it or while they are being upgraded/built. A destroyed Sentry Gun leaves 60 Metal worth of pieces, which can also be picked up by other classes as Ammo.

Unlike most other weapons, the Sentry Gun's weapons do not get affected with damage falloff from range, nor do they gain criticals. It is possible, however, to make the Sentry Gun deal mini-crit attacks and damage if its target is coated in Jarate, under the effects of the Fan O'War or Crit-a-Cola, or if the Engineer who built the Sentry Gun is close to a Soldier with an active Buff Banner – boosting the damage of each bullet to 22.

Included in the Engineer Update was an unlockable secondary replacement, the Wrangler, which allows the Engineer to take direct control of his Sentry Gun by "marking" targets manually. Doing so shuts down the Sentry Gun's automated target-lock system, but diverts the excess power from the targeting system into speeding up its firing rate, effectively doubling the damage-per-second of the Sentry Gun. The Wrangler also provides the Sentry Gun with a protective shield which absorbs two-thirds of enemy fire while the Wrangler is active. A wrangled Sentry Gun has no maximum range and does not suffer from damage falloff at longer ranges. Once the Engineer switches away from the Wrangler, however, his Sentry Gun is unable to fire for 3 seconds while its auto-lock targeting computer reboots. It is still shielded during this time.

Since the Engineer Update, players are able to haul their buildings around. An Engineer carrying his Sentry Gun moves 25% slower (225 Hammer units) and cannot fire or change weapons. However, a redeployed Sentry Gun retains its previous level and automatically sets up twice as fast. Engineers do not lose any Ammo or Metal by moving Sentry Guns. If the Engineer is killed while hauling his Sentry Gun, it is automatically destroyed along with him and gives a notification in the kill icon area of the screen. Sentry Guns under the effects of an Sapper cannot be picked up.

An Engineer is vulnerable to damage from his own Sentry Gun's bullets. For about the first 300 Hammer units of their flight, Sentry Gun rockets will pass through the Sentry Gun's Engineer without detonating, as if he were another member of the same team. However, if the rockets do strike another surface within this distance and explode, the Engineer is vulnerable to the resulting splash damage. Beyond this initial distance the Engineer is fully vulnerable to his own Sentry Gun's rockets. (The knockback from Sentry Gun self-damage enables the Engineer to perform bullet and Sentry rocket jumps, especially with the aid of the Wrangler.)


Combat Mini-Sentry Gun

The Combat Mini-Sentries as seen on the Engineer Update page.
I love that little gun!
The Engineer on his Combat Mini-Sentry Gun

The Combat Mini-Sentry Gun is a more combat-efficient version of the standard Sentry Gun, and is a component of the Engineer's Gunslinger unlock. It is a smaller Level 1 Sentry Gun outfitted with a rotating light and glowing checkered paint. Like the Sentry Gun, it can be hauled.



  • Costs only 100 Metal to place (the normal Sentry costs 130 Metal). This allows an Engineer at a full 200 Metal to build both it and a Dispenser without needing additional Metal.
  • Constructs at four times the speed of the original Sentry Gun, being armed and ready in less than 3 seconds (hitting the Sentry will NOT make it construct faster), and when deployed after hauling it will be armed in 1.5 seconds.
  • Deploys at full health and continues to gain health during construction if damaged, making it more difficult to destroy before completion.
  • Fires 50% faster than a Level 1 Sentry Gun.
  • Can rotate 35% faster than the default Sentry Gun.
  • More useful for Sentry jumping, as the firing rate and reduced damage combine to deal more knockback for an equivalent health loss.


  • Has only 100 health, compared to a Level 1 Sentry Gun's 150.
  • Not upgradable or repairable, though the owner and other Engineers can still refill its ammo.
  • Deals only 50% the damage per shot of the original Level 1 Sentry Gun. Therefore, DPS is overall lower (48 compared to the normal Sentry Gun's 64).
  • Drops considerably less Metal when destroyed.
  • Once a Sentry jump is executed, not exceptionally useful as part of a base in the new area.

Sentry Gun Levels

Level Kill Icon Health Cost Weaponry Damage Ammo

RED Level 1 Sentry Gun.png

Killicon sentry1.png 150 (effectively 450 with the Wrangler shielding) 130 Metal Semi-Automatic Firing Barrel Damage: 16
Shots per second: 4 (8 with Wrangler)
Average DPS: 64 (128 with Wrangler)
150 rounds

RED Level 2 Sentry Gun.png

Killicon sentry2.png 180 (effectively 540 with the Wrangler shielding) 330 Metal Dual Rotational Minigun Barrels Damage: 16
Shots per second: 8 (16 with Wrangler)
Average DPS: 128 (256 with Wrangler)
200 rounds

RED Level 3 Sentry Gun.png

Killicon sentry3.png 216 (effectively 648 with the Wrangler shielding) 530 Metal

Dual Rotational Minigun Barrels

Target Guided Rocket Launch Support System

Damage: 16
Shots per second: 8 (16 with Wrangler)
Average DPS: 128 (256 with Wrangler)

  • Rockets fire every 3 seconds (slightly faster with the Wrangler) dealing 53 to 150 damage on direct hit (falloff is calculated from the distance of the Engineer to the target, not from the Sentry to the target). The rockets can be reflected with the Pyro's compression blast.

200 rounds
20 rocket salvos

Combat Mini-Sentry Gun
Sentry Gun Mini.gif
Level Kill Icon Health Cost Weaponry Damage Ammo

Red Mini Sentry.png

Killicon minisentry.png 100 (effectively 300 with the Wrangler shielding) 100 Metal Semi-Automatic Firing Barrel Damage: 8
Shots per second: 6 (12 with Wrangler)
Average DPS: 48 (96 with Wrangler)
150 rounds

Related achievements

Achieved.png General

Sentry Gunner
Sentry Gunner
Accumulate 10 Sentry Gun kills with a single Sentry Gun.

Leaderboard class scout.png Scout

Gun Down
Gun Down
Destroy an active sentry gun using your pistol.

Leaderboard class soldier.png Soldier

Engineer to Eternity
Engineer to Eternity
Kill an Engineer as he repairs his sentry gun while it's under enemy fire.
Guns of the Navar0wned
Guns of the Navar0wned
Kill 5 Engineer Sentry Guns while you are standing outside of their range.

Leaderboard class demoman.png Demoman

The Argyle Sap
The Argyle Sap
Blow up an Engineer, his sentry gun, and his dispenser with a single Sticky bomb detonation.

Leaderboard class engineer.png Engineer

Texas Two-Step
Texas Two-Step
Use your shotgun to finish off an enemy recently damaged by your sentry gun.

Get 10 assists with another Engineer where a sentry gun was involved in the kill.

Best Little Slaughterhouse in Texas
Best Little Slaughterhouse in Texas
Rack up 5000 kills with your Sentry Guns.

Doc, Stock, and Barrel
Doc, Stock, and Barrel
Repair a sentry gun under fire while being healed by a Medic.

Rio Grind
Rio Grind
Perform 50 repairs and/or reloads on a Sentry gun being Wrangled by another Engineer.
Uncivil Engineer
Uncivil Engineer
Provide an enemy player with a freeze cam of you and the sentry that just killed them.

Frontier Justice
Frontier Justice
Have your sentry kill the enemy that just killed you within 10 seconds.

If You Build It, They Will Die
If You Build It, They Will Die
Haul a level 3 sentry gun into a position that achieves a kill shortly after being redeployed.

No Man's Land
No Man's Land
Use a sentry gun to kill 25 enemy players that are capturing a point.

Patent Protection
Patent Protection
Destroy an enemy Engineer's sentry gun with a sentry under control of your Wrangler.

Leaderboard class medic.png Medic

Midwife Crisis
Midwife Crisis
Heal an Engineer as he repairs his sentry gun while it's under enemy fire.

Leaderboard class sniper.png Sniper

Destroy 3 Engineer Sentry Guns.

Leaderboard class spy.png Spy

Constructus Interruptus
Constructus Interruptus
Kill an Engineer who is working on a sentry gun.
Joint Operation
Joint Operation
Sap an enemy Sentry Gun within 3 seconds of a teammate sapping another.

Update history

September 20, 2007 Patch
  • Fixed Sentry muzzleflashes not drawing unless sentry was near the map origin.

October 25, 2007 Patch

  • Engineer buildings now explode when the Engineer dies during sudden death.

November 7, 2007 Patch

  • Fixed a bug in scoring Engineer building destruction.

December 20, 2007 Patch

  • Sapped buildings now take slightly less damage from the Spy who sapped them.

February 14, 2008 Patch

  • Added server log entry for buildings destroyed by their owner
  • Fixed Sentry Gun shadows being clipped.

February 28, 2008 Patch

  • Changed Engineer buildings to detonate when a player disconnects instead of blinking out.
  • Fixed Engineer being able to detonate buildings that are being sapped.

April 29, 2008 Patch (Gold Rush Update)

  • Mapmakers can now place Engineer buildings directly into a map, with an option for them to be invulnerable

August 13, 2009 Patch

  • Fixed Sentry Guns firing at a fully cloaked Spy if they're still the closest target.

April 28, 2010 Patch

  • Killing yourself with your own Sentry Gun no longer increments the Sentry Gun's kill counter.

April 30, 2010 Patch

  • Fixed the Engineer being able to build more than 1 of each type of building.

July 8, 2010 Patch (Engineer Update)

  • Added the ability to haul or move your Sentry Gun, along with having the Wrangler control the Sentry Gun
  • Added a laser light to all sentry models.
  • [Undocumented] 'Wrenching' a Sentry Gun now upgrades, repairs and restores ammunition all at once per Wrench hit, prioritizing repairs and upgrading if not in possession of enough metal.

July 9, 2010 Patch

  • Fixed an exploit that allowed Engineers to build level 2 or 3 mini Sentry Guns.

July 13, 2010 Patch

  • Fixed an exploit where Engineers could create level 3 mini-Sentry Guns.

July 19, 2010 Patch

  • Fixed an exploit that allowed team kills with Wrangled Sentry Guns.

October 18, 2010 Patch

  • Fixed a Sentry Gun exploit that let Engineers build multiple Sentry Guns.
  • (Supposedly) Fixed Engineers being able to build level 3 mini-Sentry Guns using the Wrangler.

October 19, 2010 Patch

  • Fixed another Sentry Gun exploit that let Engineers build multiple Sentry Guns.
  • Fixed Engineers being able to build level 3 mini-Sentry Guns using the Wrangler (for real this time).

December 17, 2010 Patch (Australian Christmas)

  • Sentry Guns no longer track Your Eternal Reward Spies after they backstab someone.

January 7, 2011 Patch

  • Updated Sentry kill icons.

January 10, 2011 Patch

  • Combat Mini-Sentry is given a kill icon.

January 19, 2011 Patch

  • Fixed the mini-sentry HUD not playing the alert sound when the sentry is sapped or low on ammo.

February 3, 2011 Patch

  • Engineers who hit teammate's Sentry Guns with their Wrench now get kill assists from that Sentry Gun.

March 10, 2011 Patch (Shogun Pack)

  • Fixed the "Best Little Slaughterhouse in Texas" Engineer achievement not counting Wrangler and Mini-Sentry kills.

May 5, 2011 Patch (Replay Update)

April 17, 2012 Patch

  • Fixed being able to place buildings in nobuild zones

June 27, 2012 Patch (Pyromania Update)

  • Fixed sentry sometimes spawning in shielded mode while the Wrangler was equipped, but not deployed


  • The player has the ability to build the Combat Mini-Sentry Gun, while having any wrench equipped, by holding out the blueprints for the Sentry with the Gunslinger and then quickly switching to a wrench. The player will build a Mini-Sentry (it will still cost 100 Metal). This cannot be done vice versa (equipping the Gunslinger while having normal Sentry blueprints out.)
  • Combat Mini-Sentry Guns share gibs with standard Level 1 Sentry Guns. This means that the light and the checkerboard pattern disappear when a Combat Mini-Sentry Gun is destroyed.
  • The Combat Mini-Sentry's status in the corner of the HUD will show an upgrade progress bar despite not being repairable or upgradable.
  • The 3D sphere that represents the attack range on the Combat Mini-Sentry is smaller than the normal Sentry Gun 3D sphere; however, they both have the same attack range.
  • The damage of a level 3 Sentry Gun's rockets has falloff based on the distance of its Engineer to the target.
  • A Wrangled Sentry does not play its rocket-reloading animation.
  • Wrangling a Combat Mini-Sentry Gun might result in it remaining in the Wrangled state even when the Wrangler is not the currently active weapon. Switching back to the Wrangler corrects the problem.


Unused Sentry kill icon
  • The original Sentry Gun designs were created by Radigan Conagher in 1890.[1] The original and current designs are visually identical.
  • The Engineer apparently designed and built the final version of the Sentry Gun under contract from TF Industries in 1965.
  • The Sentry Gun makes a number of beeps every time it reverses its rotation. The number of beeps corresponds to its upgrade level, where a Level 3 turret makes three quick beeps. Additionally, the higher the Sentry Gun's level, the louder it is. A Level 1 Sentry Gun is slightly harder to hear than a Level 3 Sentry Gun; this fact can help attentive players find guarded areas.
  • The Sentry Gun's alert noise sounds slightly different when being targeted; slight clicks can be heard along with the regular beep.
  • An unused alternate kill icon for the Level 1 Sentry Gun exists in the game files, seen to the right.
  • Feign deaths produced by the Dead Ringer will not be added to the Sentry Gun kill/assist counter, but will contribute to the Best Little Slaughterhouse in Texas achievement.
  • Valve ordered and received a full size motion-tracking model of a Level 1 Sentry Gun from Weta Workshop.


Main article: Merchandise



  1. Loose Canon comic, page 8, Retrieved 2010-10-18

See also

External links