SU-122

SU-122

SU-57B

YaG-10 (29-K)

SU-122

SU-57B

YaG-10 (29-K)

USSR

II Rank

Battle rating:

AB	RB	SB
2.7	2.7	2.7

Class:

Tank destroyer

Research:9 200

Purchase:16 000

Show in game

Description

The SU-122 was a World War II-era Soviet self-propelled assault gun. Mounted on a T-34 medium tank chassis, the main armament consists of a 122 mm M-30S howitzer. After the German Sturmgeschütz III assault guns proved successful, the Soviet High Command became interested in this concept. Compared to conventional tanks, assault guns had certain advantages. Their lack of a turret allowed for a lower production cost. On the same chassis, they could be equipped with bigger and more potent weapons and constructed with a larger fighting compartment. However, unlike conventional tanks, assault guns usually aim by orienting the entire vehicle, making them less effective in close-quarters fighting.

Introduced in the Closed Beta Test for Ground Forces before Update 1.41, the SU-122 is a truly unique vehicle. Its formidable gun is its primary feature, but considering the incredibly long reload time, players need to make every shot matter. It also possesses formidable frontal armour that can withstand most shells at its rank. However, due to its high shell drop, it is also very difficult for it to hit targets from a distance during battles; therefore, a great deal of experience is required to operate this vehicle well.

General info

Survivability and armour

Armourfront / side / back

Hull45 / 45 / 45

Turret45 / 45 / 45

Crew5 people

Visibility76 %

The front glacis of the tank is very strong against tanks of similar BR. Sloped at about 50° with 45 mm of steel, and an even stronger lower glacis reaching up to 100 mm of armour with an angle about 20-70°. This allows it to face most enemies with lighter armament frontally and "tank" their shells.

Unfortunately, its side armour will fail to stop most shells fired directly at it, so angling should be minimal as to avoid being obliterated by a patient sniper.

Due to frontal armour being nigh impenetrable for many light and medium tanks until BR 3.0, most players will aim at your gun mantlet and very likely penetrate it, breaking the gun breech. Note that if you lose your gun and/or tracks, you're losing all means of fighting back or retreating. Having 5 crew members is not spectacular, but it still gives you a fighting chance if 1 or 2 crew members are knocked out.

Armour type:

• Rolled homogeneous armour
• Cast homogeneous armour (Gun mantlet, Driver's hatch)

Armour	Front	Sides	Rear	Roof
Hull	45 mm (49-50°) Front glacis 45-100 mm (21-69°) Lower glacis	45 mm (17-41°) Top 45 mm Bottom	45 mm (47-48°) Top 45 mm (48°) Bottom	20 mm
Superstructure	45 mm (49-50°)	45 mm (17-18°)	45 mm (12°)	20 mm
Cupola	45 mm	45 mm	45 mm	20 mm

Notes:

• Suspension wheels and tracks are 20 mm thick.

Mobility

Speedforward / back

AB60 / 10 km/h

RB and SB55 / 9 km/h

Number of gears5 forward

1 back

Weight30.9 t

Engine power

AB954 hp

RB and SB500 hp

Power-to-weight ratio

AB30.9 hp/t

RB and SB16.2 hp/t

Game Mode	Max Speed (km/h)		Weight (tons)	Engine power (horsepower)		Power-to-weight ratio (hp/ton)
	Forward	Reverse		Stock	Upgraded	Stock	Upgraded
Arcade	60	10	30.9	710	954	22.98	30.87
Realistic	55	9		442	500	14.3	16.18

The mobility of the SU-122 is excellent for a vehicle with such protection and firepower. On hard and/or flat surfaces it can easily reach 50 km/h after some acceleration which is comparable to even some light tanks. Thus it is able to rush to required locations in urban maps quickly. For off-road environments, the speed will drop considerably, although still satisfactory. The hull traverse is usable, but it may only be barely enough to keep up with a small, fast tank (e.g. M3 Stuart) circling you in close proximity. The reverse speed is extremely slow and will not get you out of a dangerous situation quickly, although your armour might save you.

Modifications and economy

Repair costBasic → Reference

AB600 → 742

RB660 → 816

SB801 → 990

Total cost of modifications8 390

9 370

Talisman cost640

Crew training4 500

Experts16 000

Aces160

Research Aces190 000

Reward for battleAB / RB / SB

40 / 60 / 70 %

118 / 118 / 118 %

Modifications

Mobility	Protection	Firepower
Tracks Research: 420 Cost: 470 65 Suspension Research: 470 Cost: 530 75 Brake System Research: 470 Cost: 530 75 Filters Research: 700 Cost: 790 110 Transmission Research: 910 Cost: 1 000 140 Engine Research: 910 Cost: 1 000 140	Improved Parts Research: 420 Cost: 470 65 Improved FPE Research: 470 Cost: 530 75 Crew Replenishment Research: 700 Cost: 790 110	Horizontal Drive Research: 420 Cost: 470 65 122mm_HEAT_ammo_pack Research: 420 Cost: 470 65 Adjustment of Fire Research: 470 Cost: 530 75 Elevation Mechanism Research: 700 Cost: 790 110 122mm_ussr_Smoke_ammo_pack Research: 910 Cost: 1 000 140

Armaments

Main armament

122 mm M-30 howitzer

Ammunition40 rounds

Reloadbasic crew → aces

23.6 → 18.2 s

Vertical guidance-3° / 25°

Horizontal guidance-10° / 10°

The SU-122 uses two types of shells: the HE and the HEAT.

The HE shell isn't the strongest at the BR, but it is strong enough to defeat most tanks roofs and destroy them via overpressure. It doesn't necessarily have to be turret roof, as even hull roof penetration generally leads to the tank's demise. Unfortunately, the HE shell requires some extra time to aim, as quite often hits to the frontal armour of enemy tanks does nothing, particularly in an up-tier. Avoid firing directly at tanks cannons, as it might reduce the splash damage from the shell and let them survive the shot. Nonetheless, it is a very strong tool against teams made of light or medium tanks.

The HEAT shell can penetrate pretty much anything the SU-122 can face, but has a very focused shape of damage, therefore it is likely that the enemy tank will survive the attack if it is wide enough. The shell also has very low muzzle velocity and is very difficult to aim at medium to long range without aim assist or rangefinding crew skill (which normally players do not have yet). It is very practical to use in urban combat, where you do not have any time to think about where to aim and there is no telling what you will face after cutting a corner.

Either shell will obliterate open-topped tanks if they land on them due to overpressure damage.

Unfortunately, since the SU-122 does not have a machine gun and has a low profile, it must first ram any foliage and fences or allow its opponent to fire at it first in order to attack tanks hiding behind them, as otherwise the shell fuse will react to them and explode. Extra care should be taken, if your current position has a forest or a transparent fence.

122 mm M-30					Turret rotation speed (°/s)					Reloading rate (seconds)
Mode	Capacity	Vertical	Horizontal	Stabilizer	Stock	Upgraded	Full	Expert	Aced	Stock	Full	Expert	Aced
Arcade	40	-3°/+25°	±10°	N/A	13.21	18.28	22.25	24.55	26.12	23.66	20.93	19.29	18.20
Realistic					8.93	10.50	12.75	14.10	15.00

Ammunition

Penetration statistics
Ammunition	Type of warhead	Penetration @ 0° Angle of Attack (mm)
		10 m	100 m	500 m	1,000 m	1,500 m	2,000 m
OF-462	HE	37	37	37	37	37	37
BP-460A	HEAT	160	160	160	160	160	160

Shell details
Ammunition	Type of warhead	Velocity (m/s)	Projectile mass (kg)	Fuse delay (m)	Fuse sensitivity (mm)	Explosive mass (TNT equivalent) (kg)	Ricochet
							0%	50%	100%
OF-462	HE	515	21.76	0	0.1	3.67	79°	80°	81°
BP-460A	HEAT	335	13.4	0.05	0.1	2.73	62°	69°	73°

Smoke shell characteristics
Ammunition	Velocity (m/s)	Projectile mass (kg)	Screen radius (m)	Screen deploy time (s)	Screen hold time (s)	Explosive mass (TNT equivalent) (g)
D-462A	515	22.32	20	5	25	50

Ammo racks

Ammo racks of the SU-122

Full ammo	Ammo part	1st rack empty	2nd rack empty	3rd rack empty	4th rack empty	Visual discrepancy
40	Projectiles Propellants	29 (+11) 29 (+11)	17 (+23) 17 (+23)	8 (+32) 8 (+32)	1 (+39) 1 (+39)	No

Notes:

• The SU-122 uses two-piece ammunition, composed of projectiles (yellow) and propellant bags (orange). Both have separate racks.
• Racks disappear after all shells in the rack have been loaded or fired.

Usage in battles

The main feature of this SPG is a powerful gun, but make good use of the first shot. It is very hard to hit targets from over 500 m in realistic and simulator battles since shell velocity is slow and shell drop is significant. The cannon's HEAT shell has excellent destructive power and higher penetration than its HE shell (and in fact can penetrate almost anything it will face), but it also has a slower shell velocity than the HE shell. Practice makes aiming at long distances easier, but it is still recommended to stay at close to medium range when possible. One tactic would be to rush an enemy tank and shoot it at point-blank range, but this only works if there are no other enemy tanks nearby because with an untrained crew it can take up to 33 seconds before the SU-122 has reloaded.

This slow reload rate also means that the SU-122 cannot effectively deal with multiple enemies at the same time. Therefore, team play is almost a necessity. If you do not have a squad to play with and you do not trust your teammates, try to keep hostile tanks on your front and avoid overextending into the enemy territory, where your teammates will be unable to keep enemies off your sides by just being there. This is especially important since, of course, the SU-122 is a case-mate tank destroyer without a traversable turret. The vehicle's sides are flat and thus incredibly vulnerable to enemy flankers, and although the side armour itself can stop glancing hits with small-calibre rounds, they will not stop shells from enemy medium tanks or SPG. It is particularly important to keep a constant lookout for enemy flankers when fighting at closer ranges where the enemy can sneak up without you noticing.

When the loader(s) is wounded or knocked out, the long reload time will become even longer, and playing effectively with the SU-122 then becomes very difficult. So, avoid exposing the loader to enemy fire when possible. Thankfully, the SU-122 has a decent armour layout. Its front armour, while not invincible, can still protect against some low-rank guns, and the gun mantlet is very strong. The tank also has a fairly small silhouette. Nevertheless, the frontal armour is not sufficient against high-rank guns, like the German 50 mm KwK39 or SPG cannons in general, and, due to the crew layout within the tank, a shot to the left side can knock out three of the five crew members--including the driver and the gunner. This is a debilitating hit and will often result in the SU-122's outright destruction. If possible, position your tank so that it is difficult for the enemy to hit this left side of your vehicle.

The SU-122 plays well has a hull-down tank destroyer: this is where its powerful gun shines and where the issues caused by its long reload are minimized. If choosing this playstyle, the player should remember that the SU-122 suffers at long ranges due to its slow shell velocity. Therefore, choose hull-down positions so that the enemy will appear at close or medium ranges. Also be aware that the SU-122 has bad gun depression, which can make shooting over ridgelines very difficult.

Another possible playstyle is close range brawling. In this playstyle, it is important to work with teammates, since the lack of a turret means that the SU-122 can be easily ambushed and can only deal with enemies from the front. It is aided by good mobility and great acceleration, which are both useful qualities to have in close-range fighting, as, if necessary, it can ram enemy tanks and cling onto them, rendering them unable to fight properly or to run away (unless someone else saves them).

Against the SU-122

An experienced SU-122 commander can maximise its armour and firepower, making it not any less fearsome than a B1 ter. So it is important for players to know the weaknesses of the SU-122.

• Light tanks & SPAAS (M3/M5, Crusader, AB 43, etc.): these vehicles are poorly armoured but have great mobility. Use their speed and agility to your advantage: do not expose yourself face to face against a SU-122 unless it is reloading/disarmed, its HE shell can easily destroy you with overpressure. If you must fight it frontally, either destroy both of its tracks so it cannot move or damage its gun barrel/breech (this is considerably harder as the gun will be constantly aiming around, and the target is small). Multiple shots might be needed if your calibre is small, in the mean time conceal yourself if it starts aiming at you. You can try scraping behind a cover and exposing a small part of your tank to trick it into firing, and if you manoeuvre/dodge properly it is likely to miss. Once it is immobile, disarmed or reloading, flank to its side/rear. The side is generally a better choice as there is a flat armour right above the track to shoot at, while the hull rear is sloped and can resist some small-calibre shells, meaning only the rear of the fighting compartment is vulnerable. If you do not have lots of penetration (e.g. Flakpanzer 38, M3 Stuart, etc.), target said flat side armour and knock out either the driver or the engine first to make sure it cannot move in the following seconds. Then take your time and knock out the remaining crew members.
• Medium tanks (Pz.III J, Chi-Ha Kai, M3 Lee, etc.): medium tanks receive better firepower at the price of worse mobility, and this may make it harder to kill a SU-122. Since you do not have the great speed light tanks sport to freely manoeuvre around the target, you must get used to quick and precise targeting to aim at whichever weak spot is presented to you. In a frontal encounter, although you have a more powerful cannon, it is still not likely to go through the SU-122's frontal armour, but you need fewer shots to break its tracks, gun barrel or gun breech. Remember to conceal yourself properly if you think it will fire first. Do not expose an angled part of your tank hoping to "side-scrape" to lure its shots, your crew/modules will likely get destroyed by overpressure. When you are at its side, you can target the larger slightly-angled armour of the fighting compartment to knock out its closely-packed crew, if you have explosive shells. If not, again target driver/engine first.
• Heavy tanks/ tank destroyers (Matilda, M4A3 (105), Marder III, etc.): these tanks either have the armour to take some hits, or the firepower to wipe out almost all opponents, making them easier to deal with a SU-122. Nevertheless, care should be taken as its HE shell is still a huge threat. Since heavy tanks have thicker armour, there is a chance that the SU-122 fires at them where overpressure doesn't work. If that is the case, break its tracks or cannon during its reload, and flank to its side for the kill. Tank destroyers at this BR can frontally penetrate the T-34 chassis even from a distance, but they are usually weakly protected. The best tactic is to keep your distance and destroy the SU-122 once it reveals itself, as it has slow muzzle velocity and curved trajectory making it bad at distant shots. But do cover yourself if you cannot shoot immediately, you cannot take its blow either.

Pros and cons

Pros:

• Great firepower, capable of destroying tanks with a single shot when user takes time to aim
• Sloped front glacis, while not outstanding, is still capable of bouncing shells from most low-rank guns
• Mantlet is very strong and shells can bounce off it
• Good mobility and acceleration (T-34 chassis and engine)
• Somewhat low silhouette
• Two respawns in SB mode

Cons:

• Very long reload time, increased if the loader is wounded
• Ineffective armour against high-rank guns
• Enemies often aim for the gun breech since it is often the only thing they can penetrate, and damage resets the reload timer
• Gun mantlet can limit the view when in sniper mode only when in SB Mode
• Limited horizontal gun traverse
• Poor gun depression
• Poor shell ballistics (low projectile velocity and early projectile drop) makes it near-impossible to hit moving targets and targets beyond 500 m
• Slow reverse speed, can be fatal

History

Development

The success of the Germans StuG III and other self-propelled assault gun took the Soviet High Command's interest on the concept. Self-propelled guns were generally considered cheaper and more easily produced compared to regular tanks due to the lack of turret, plus it could be made with a large fighting compartment and bigger guns than those that could be mounted on turrets, the only drawbacks to the designs were limited traverse of the gun so it would do poorly in close-quarters situations.

On the 15th April, 1942, the Soviets asked design bureaus to begin development of assault guns using a wide selection of armament ranging from their 76.2 mm ZiS-3 field guns, 122 mm M-30, and 152 mm ML-20 howitzers. The prototype assault gun was armed with the 122 mm and was quite similar to the StuG III's design, designated the SG-122, of which only 10 were made due to reliability issues. The next step was to take the standard issued Soviet tank, the T-34, and convert that into the assault gun. The prototype, U-34, was created in summer of 1942 in the Uralsky Machine Building factory by N. W. Kurin and G. F. Ksjunin. It initially had the same armament of 76.2 mm, but it was 70 cm lower than the regular T-34 and had more armour at a lighter weight, this did not enter production. Another work was done to combine the U-34 features with the SG-122, this was completed in around late summer of 1942 and featured the U-34 chassis with the 122 mm armament placed on with the least modifications possible to keep the design affordable and easy to produce. This new design, now the U-35, was created on November 25, 1942, and was sent for evaluations. There were faults discovered in the elevation mechanism, loading system, and ventilation for the crew. Despite these flaws, the vehicle was accepted into service first as the SU-35 but then renamed the SU-122. Several modifications were made to the vehicle during production, such as simplifications to the design, modified interior layout, removed vision slots, and added a commander's periscope. The production began in December 1942 and continue on until summer of 1944 with 1,150 total unit produced.

Design

The vehicle was based off the T-34 chassis, so it uses the same running gear, engine, suspension, and tracks as the T-34. This is consistent with the concept of utilizing the chassis of proven vehicles and converting them into other uses. The design mounted the 122 mm M-30 howitzer, which was made for infantry support in a role similar to the StuG III in German usage. The M-30S howitzer could be elevated or depressed between −3° and +26° and had 10° of the traverse. The design had no armour advantage over the standard T-34 with 45 mm thick frontal armour to keep production simple. The design had a crew of five: a driver, a gunner, a commander and two loaders to load the 122 mm shells.

Combat usage

The first few SU-122s created were sent to training centres and to two combat units, the 1433rd and 1434th self-propelled artillery regiments. Each regiment was intended to have two batteries of four SU-122s and four batteries of four SU-76s. Thirty of such self-propelled artillery regiments were planned to be raised in the armour and mechanized corps. In January 1943, the 1433 and 1434 regiments were sent to Leningrad near the Volkhov Front to support the 54th Army. These regiments and their self-propelled guns first saw action on January 14 in the Smierdny region. Combat experience showed that the best deployment of the SU-122s was about 400 to 600 m behind advancing tank units, to which it was sometimes reduced to just 200 m minimum distance. The mixed deployment of the SU-76 and the SU-122 was a failure and the organization was changed. The new system had two batteries of SU-76 and three batteries of SU-122s for 20 vehicles, this was changed again in April for separate regiments for SU-76s and SU-122s (called "light" and "medium" respectively). The medium self-propelled artillery regiments had four batteries of four SU-122s each for 16 vehicles. An additional SU-122 or T-34 was added as a commander for the regiment, along with a BA-64 armoured car for reconnaissance duties. This organization of the self-propelled artillery regiments stayed until the beginning of 1944 as newer and better self-propelled guns such as the SU-85, ISU-122, and ISU-152 were being produced, when the SU-122 was beginning to be phased out as well.

The SU-122 in combat proved very effective in its role as direct fire support on strongholds. The high-power high-explosive rounds create a massive concussion blast on impact and may be powerful enough to even knock the turret off a Tiger I tank. Until May 1943, only the HE rounds were available for the 122 mm gun, but the BP-460A HEAT rounds were introduced on that month that could theoretically penetrate any armour the German have on their tanks, but the HEAT round's primitive design and fuse, adding the gun's inaccuracy, caused the SU-122 to not be an effective tank destroyer.

The SU-122 was never mass-produced in multiple variants, however, some were converted into prototypes. The SU-122M had a larger compartment and newer D-11 gun, and the SU-122-III had an even lighter gun than the D-11, but was unsuccessful due to unreliability. Both of these were cancelled when production priorities went to the SU-85 design.

Survivors

Only a small number of SU-122s survived the war, with only one known example on display at the Kubinka Tank Museum.

Archive of the in-game description

This SPG armed with a 122 mm M-30 Mod. 1938 howitzer was developed in October-November 1942 to support and escort tanks. In December of the same year, it entered production and was put into service. The SPG was built on a T-34 chassis with an armoured cabin containing the driving compartment and the fighting compartment. To protect the howitzer's recoil mechanism, a large forward-extending armoured mantlet was used which swung with the weapon. The gunnery equipment could be used to fire both directly and from cover. The howitzer's ammunition load of 40 shots included high-explosive fragmentation shells and hollow-charge projectiles. The vehicle's undercarriage differed from the T-34 in the strengthened head assembly of its suspension. A 9R radio set was mounted on the SPG, along with the TPU-3-BisF intercom. The vehicle was produced throughout 1942-1943, with 638 manufactured in total. Throughout its production, a large number of modifications were implemented with the aim of improving the vehicle's quality and simplifying its manufacturing. Work performed on perfecting the manufacturing and assembly technologies involved reduced the labour costs of its production by 15%. The SU-122 was put into service in SPG regiments in quantities of up to 16 vehicles per regiment. The SPG's flaws were: its small horizontal firing angle and complex aiming; long barrel length complicating manoeuvring on rough terrain and in urban areas; low rate of fire in combat; relatively small on-board ammunition capacity; and lack of a machine gun for self-defence. In spite of these flaws, the SU-122's high firepower, manoeuvrability and defensive capabilities made it a dangerous opponent in battle.

Media

Skins

• Skins and camouflages for the SU-122 from live.warthunder.com.

See also

Links to the articles on the War Thunder Wiki that you think will be useful for the reader, for example:

• reference to the series of the vehicles;
• links to approximate analogues of other nations and research trees.

External links

• [Ace Tanker] Vasily Krysov
• [Wikipedia] SU-122