Tunder S14

The Tunder S14, or GROM S-14, is a 9x39mm bullpup assault rifle featuring an integrated grenade launcher, that appears in S.T.A.L.K.E.R.: Shadow of Chernobyl, S.T.A.L.K.E.R.: Clear Sky, S.T.A.L.K.E.R.: Call of Pripyat, and S.T.A.L.K.E.R. 2: Heart of Chornobyl.

Appearances

Shadow of Chernobyl

An assault rifle combined with a grenade launcher. It is a very good type of assault rifle for the Zone conditions: it is compact, reliable, but universal and powerful. The Tunder S14 is one of the favorite rifles of the military stalkers.
― In-game description

The Tunder S14 is very accurate at close range and fairly accurate at long ranges, in the right hands one could pop headshots at long ranges using the iron sights. The weapon itself is very powerful and could easily rip apart the armor of an Exoskeleton. Combined with its grenade launcher, it's a weapon for all occasions. Its only drawbacks are that its small magazine limits its firing rate, it has lower accuracy than other high-end assault rifles, it is very prone to jamming, and most of its ammunition is heavy weighing at .70kg per box which would also restrict the player from carrying lots of equipment.

Acquisition

In Shadow of Chernobyl, the Tunder S14 isn't as widespread as most assault rifles. It is the weapon of choice of most Duty veterans and experts. Spetsnaz experts may use this weapon, along with Military Stalkers.

The Tunder S14 is sold by Professor Sakharov after retrieving the Documents from Lab X16, and Colonel Petrenko by default, although the weapon is available for cheaper after the mission Obtain an Bulldog 6 from Freedom has been completed.

General Voronin will reward the player with a Tunder S14 for successful completion of his non-repeatable mission to Neutralize the bandit. By doing Voronin's other repeatable side-missions, it's possible to earn an unlimited supply of SP-6 ammo and VOG-25 Grenades. This is a good way to gear up for the endgame.

It can be found in the following locations:

• Skull's group uses this weapon, and if one completes Lukash's mission to Destroy the Duty company, they can find several of these weapons and a varying amount of 9×39mm rounds depending on game difficulty.
• One is hidden in a restroom inside Lab X-16, to the left when entering the room with the controller and Ghost's body. It is found inside a toilet tank.
• Two stashes in Army Warehouses contain a Tunder S14: Chest with goods (Army Warehouse) and Secret stash in the log (2). Several stashes in the area contain suitable ammo.
• Duty experts in Pripyat using the PSZ-9Md Universal Protection all carry the weapon.
• Carried by a few Duty members. This includes the Warrant Officer, some experts guarding the Duty base and Ivantsov.

Unique variants

• "Tunder" 5.45 - a unique Tunder S14 modified to fire 5.45x39mm ammunition instead of 9x39mm.

Clear Sky

This assault rifle, combined with a grenade launcher, is a great solution for the Zone's challenges: a compact, reliable and powerful all-purpose weapon. Particularly popular with military stalkers. Uses 9x39 mm ammo and VOG-25 grenades.
― In-game description

In Clear Sky, the Tunder S14 assumes a slightly new design, with brown synthetic parts. It is an overall great assault weapon, where it can be upgraded for superior firing rate and stability and its magazine can also be expanded by 10 rounds. It can also be upgraded to use 5.45×39mm rounds instead of 9×39mm rounds, making it a more economical weapon, though the 9×39 ammunition has much better armor penetration. The underbarrel grenade launcher gives user options and when fully upgraded, the Tunder can obliterate unlucky stalkers at close range in a matter of seconds.

The Tunder S14 only has one upgrade tree instead of the usual two for assault rifles and has no "accuracy" upgrade tree, only the rate of fire upgrades. It can accept a PSO-1 scope and silencer by default, though it makes a poor sniper analogue since it has no accuracy upgrades and unimpressive base accuracy. Fully upgraded, the Tunder S14 has the fourth highest firing rate, just behind an upgraded RP-74, GP37, and the FT-200M.

Acquisition

Unlike in Shadow of Chernobyl, the weapon is extremely rare. It's almost exclusive to the Duty faction, and it is only held by Duty's powerful Exoskeleton units.

The Tunder S14 is sold by Mitay provided the player has given Lingov's PDA to Chekhov and Duty controls the entirety of the Agroprom. He sells it regardless of membership status, but being a Duty member allows the player to buy it for cheaper. One is also given to the player for free if they join Duty.

A Renegade trader uses this weapon in the Red Forest, and Monolith experts sporting Exoskeletons and some Spetsnaz troopers use this weapon. A Tunder S14 can be found in a stash called "Stash in peasant's shed" at the Army Warehouses, within the Bloodsucker village. Coordinates can be gained from fallen Stalkers in both the Red Forest and Army Warehouses.

Upgrades

Bolt mechanism modification (3000 RU) Fire rate +10% A technological modification of the bolt mechanism allows for a higher rate of fire.	Improved mechanism balance (4500 RU) Fire rate +25% Better balancing of the mechanism's working parts allows the weapon's rate of fire to be significantly increased.	Barrel cooling (7500 RU) Fire rate +30% A barrel cooling system allows the weapon's rate of fire to be increased further with no risk of barrel deformation.
Operating rod modification (3000 RU) Recoil -20% Mounting an operating rod compensator allows recoil to be reduced.
Barrel modification (3000 RU) Flatness +20% Replaces the standard barrel with a lightweight version.	Barrel modification (4500 RU) Recoil -20% Installing a muzzle brake allows recoil to be reduced significantly.
Assault magazine (3000 RU) Mag. size +10 A much larger magazine designed specifically for assault operations.
5.45x39 mm сaliber (3000 RU) Caliber 5.45x39 The barrel is replaced and gun parts are adjusted to the new caliber. This replacement can only be performed once.

Unique variants

• Tunder S14sn - a variant that was cut from the final release of the game.

Call of Pripyat

This assault rifle combined with a grenade launcher, which is similar to the AKM series, was specifically developed for rapid response units. The main differences are its 9x39 caliber ammunition, bullpup layout and extensive configuration options. This weapon is highly valued by military stalkers due to its ability to kill enemies wearing body armor behind improvised cover at a distance during urban combat, as well as its excellent stopping power.
― Call of Pripyat in-game description

The Tunder S14 returns in Call of Pripyat as, once again, a rare assault rifle. The Tunder now cannot sport nor be upgraded to mount a PSO-1 scope as it did in Clear Sky, which limits its potential effectiveness at long range, although it can still mount a silencer. This is offset by the fact that the Groza is one of the best close-quarter combat weapons available. Its caliber, paired with its high damage, manageable recoil and firing rate make it a great weapon for urban combat and the integral GP-25 Koster makes it even more deadly against clusters of enemies and against dangerous mutants like the Pseudogiant and Chimera.

However, the Tunder has surprisingly low reliability (probably lowest from any Warsaw Pact weapons), making it a questionable choice for a player who wishes to compromise power, accuracy and reliability of their weapon and also due to very heavy ammunition (30 9x39 bullets weighs 0.7 kg, 4 times more than the same amount of 5.45 and 5.56 bullets), one may prefer to use a 5.45 or 5.56 weapon instead.

Acquisition

Duty forces rarely wield the weapon, and Military units instead rely on the AC-96/2 and the SA Avalanche for assault rifles. Loners will not wield the weapon until much later in the game, where it can be sometimes found in the hands of those wearing Exoskeletons. Monolith experts also make use of this weapon. Ammo can be rather scarce, but if one completed Trapper's mutant hunting quests, ammunition will be deposited into the player's personal locker in Yanov station daily, including 9x39 ammunition.

The Tunder S14 is rarely sold by Owl at the beginning of the game (5% of chances of spawning in his inventory), or frequently sold after obtaining the achievement One of Ours. It is also sold by Hawaiian after getting the achievement A Friend of Duty. One can be obtained by selling General Tachenko's PDA to Shulga. The weapon is also wielded by Colonel Kovalsky and Lieutenant Kirillov.

It can be found in the following locations:

• Duty warehouse — There is one Tunder S14 inside the warehouse, among other things, along with ammunition for it. The warehouse can only be unlocked by completing the mission Duty warehouse.
• Volkhov AA Complex — In between the driver and passenger seats of the van parked outside (includes several 9×39mm rounds).
• Kopachy — Atop the roof of the grey house in the south eastern corner of the village (includes 90 9×39 rounds, a GP-25 Koster grenade launcher, and 2 VOG grenades).
• Jupiter plant — At the bottom of a flight of stairs behind a Burnt Fuzz, in the northern stairwell of the administrative section where the Administrative documents are found.
• Pripyat — In a car along with 9x39 rounds near the Kindergarten.
• Ventilation complex — On the northern side in a broken wall (including a silencer).

Upgrades

Rapid automatic release (1000 RU) Fire rate +10% Despite the name, it is the bolt that is replaced, as it has to endure the consequences of an improved rate of fire.	Addition of a blowback speed reduction device (1600 RU) Recoil -20% A special component installed into the bolt mechanism to soften bolt movement and reduce recoil. Protective bolt section sputter (1600 RU) Reliability +15% Sputter protects weapons from early wear.	Short movement gas piston (2200 RU) Fire rate +25% A replacement of the automatic parts is more of an optimization than an improvement of the gas piston. Provides considerable increase in the weapon's rate of fire. Change to a roller system with a semifree bolt (2200 RU) Accuracy +30% Often used in modern weaponry, a roller locking system reduces recoil and improves groupings.
Mobile counter-weight (1000 RU) Recoil -10% Installation of a mobile component into the stock, which creates a counter-effect when the weapon is fired.	Installation of a barrel closing device (1600 RU) Flatness +20% A special component seals the barrel in an airtight manner to increase pressure when a shot is fired.	Addition of a blowback speed reduction device (2200 RU) Recoil -30% A special component installed into the bolt mechanism to soften bolt movement and reduce recoil. Addition of a stopping device (2200 RU) Accuracy +30% A synthetic component immediately in front of the bolt movement area, which compresses it significantly to improve firing accuracy.
Additional return spring (1000 RU) Recoil -10% Installation of an additional spring with a reverse coil to reduce recoil without sacrificing flatness.	Addition of a balancing element (1600 RU) Accuracy +20% A synthetic element installed onto rods ensures that they move strictly as intended, increasing accuracy. Protective return mechanism component sputter (1600 RU) Reliability +20% Protective sputter increases reliability and, more importantly, ensures airtightness, which prevents energy dissipation.	Installation of a distribution link (2200 RU) Fire rate +25% A link that is opened by gases and closed by the return mechanism itself, which allows part of the gas energy to be used to operate the return mechanism. Return mechanism sleeve thickener (2200 RU) Flatness +30% Thickening of the sleeve allows barrel pressure to be increased, improving bullet speed.
Addition of counter-weight to the steel box (1000 RU) Recoil -10% A simple addition of weight to the front of the receiver to reduce recoil.	Ergonomic receiver shape (1600 RU) Handling +15% A more convenient handle shape, which allows for better handling of the weapon when firing on the move.	Modular receiver (2200 RU) Reliability +25% A modification used exclusively for barrels with solid bullpup receivers, which simplifies maintenance of the weapon. Smoothing receiver groove and indent sputter (2200 RU) Flatness +30% This sputter prevents the barrel from overheating, removes manufacturing defects and significantly increases the barrel's life cycle.
Increased magazine capacity (1800 RU) Mag. size +10 Replacing a standard magazine with a bigger one.

Unique variants

• Storm - a unique Tunder S14 modified to fire 5.45x39mm ammunition, making it very similar to the "Tunder" 5.45 from Shadow of Chernobyl. As a result of its ammunition, it features a better fire rate, reliability and bullet velocity than the base model but lower damage, and can mount a PSO-1 scope and any of its variants unlike the stock Tunder S14. It can be acquired from Nimble for 20000 RU.

Heart of Chornobyl

Automatic rifle and grenade launcher system – an assault rifle configuration that can come in quite handy in the Zone. A good fit for lovers of ultimate firepower at both short and medium distances.

Acquisition

Upgrades

Sounds

Gallery

Shadow of Chernobyl

The Tunder S14 in first-person view

Iron sights

Reloading

The Tunder S14 with an attached silencer

The Tunder S14 with an attached PSO-1 scope

First person view with the grenade launcher's ladder sight raised

The launcher's ladder sight

Reloading the grenade launcher

Third person view

Shadow of Chernobyl's world model, note the all-synthetic parts.

Clear Sky and Call of Pripyat

The Tunder S14 in first-person view

Iron sights

Reloading

The Tunder S14 with an attached silencer

The Tunder S14 with an attached PSO-1 scope

The weapon's world model as seen in Clear Sky and Call of Pripyat.

Behind the scenes

• The weapon's in-game name, "Tunder", is a reference to the weapon's real-life name, "Groza", which means "thunder" or "thunderstorm" in Russian.
• The weapon is based on the 9x39-over-40mm configuration known as the OC-14-4A. However, the in-game model has an RPK-style receiver, while the real-life weapon uses an AK-style receiver. The weapon in Shadow of Chernobyl also appears to use STANAG magazines.
  • In reality, the Groza in this configuration cannot mount a sound suppressor, as it blocks the launcher's barrel, which would lead to it breaking the silencer when fired. The launcher in real life can be detached, however, and then a suppressor can be safely used. A vertical foregrip is attached to the barrel when the grenade launcher is removed to give the user's non-trigger hand a convenient place to hold the weapon.

Game differences=

• In Shadow of Chernobyl, if the player has loaded a VOG-25 Grenade in the grenade launcher, and switches from the grenade launcher to the assault rifle, a spinning grenade can be seen clipping through the grenade launcher.
  • The reload animation always shows the player loading a VOG-25R Grenade into the launcher, regardless of the grenade type being loaded.
• In Clear Sky and Call of Pripyat, the first-person model depicts the weapon having its magazine inserted far too deep into the magwell; this can be noticed when reloading. In addition, the magazine protrudes from the right side of the receiver, though this is not visible without using console commands.
• In Clear Sky, the Tunder could be originally modified for sniper fire at the cost of firing rate and its magazine would be reduced to 15 bullets. When patch 1.5.05 was released however, this modification tree was removed and upgrades fully focused on firing rate and reduced recoil. This modification tree is brought back to Call of Pripyat, but without the drastic penalties to firing rate and capacity.
• In Call of Pripyat, a static, non-obtainable Tunder S14 can be seen in Shulga's room in Yanov station with a PSO-1 scope and a silencer attached to it, despite the fact the weapon cannot mount a scope in-game (although its unique variant, the Storm, does).
• In Heart of Chornobyl, the Grom S-14 is misspelled as "Grim" in the game files.

Development

The Tunder S14 is one of the first weapons that appeared in the S.T.A.L.K.E.R. series. It appears as a usable weapon in Build 1098 with a completely different model, but disappeared until Build 1935, where it appeared with its final model.

Also, in Build 1935, its reload speed was almost as slow as that of the SVUmk-2 sniper rifle. It was sped up in the final release, likely due to its high firing rate, low magazine capacity, and assault rifle balance.

The Groza in Build 1098

World model of 1098 type Groza

The Groza in earlier builds