BM-31-12

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BM-31-12

Template:GarageImage BM-31-12.jpg

BM-31-12

USSR

III Rank

Battle rating:

AB	RB	SB
4.0	4.0	4.0

Class:

PREMIUM

Tank destroyer

Purchase:Bundle or Gift

Show in game

 Description

The BM-31-12 is a premium gift rank III Soviet tank destroyer with a battle rating of 4.0 (AB/RB/SB) also known as "Andryusha". It was introduced during May 2023 as part of the 2023 Legends of Victory event. A highly unusual vehicle, reminiscent of its smaller brother, the BM-13N. Not only is its truck-based configuration not the most common, but it also uses 12 x 300 mm M-31-UK rockets as its main armament, has limited traverse, has only 2 crew members, and a gun depression of +8°. The last is somewhat compensated by its ability to lean forwards with a hydropneumatic suspension system usually found on higher rank vehicles. Its gameplay is best compared with its smaller sibling, the BM-13N "Katyusha".

The Andryusha is an artillery piece, belonging more in an artillery formation than in a tank battle. One should stay at a distance from the enemies since its rockets have a blind zone of about 300 m in front of the truck when moving on a flat surface.

 General info

 Survivability and armour

Armourfront / side / back

Hull4 / 4 / 4

Turret0 / 0 / 0

Crew2 people

Visibility75 %

Being designed for rear-line support, the BM-31-12 lacks any real armor. Being a simple truck, even rifle-calibre machine gun can penetrate the vehicle and knock out the two crew members. Therefore, the vehicle is extremely vulnerable to overpressure (HE shells, rockets, bombs and artillery strikes) as well as strafing aircraft and tank coaxial/roof machine guns. It is best to play at a distance from the frontline and with some cover nearby to retreat behind once the enemy presence increases, as your mobility isn't great either.

Armour type:

• Rolled homogeneous armour (Roof and window covers)
• Structural steel (Chassis and driver's cabin)
• Gun Steel (Rocket launcher)

Armour	Front (Slope angle)	Sides	Rear	Roof
Chassis	30 mm	30 mm	30 mm	5 mm
Cabin	1 mm (77-86°) Hood 4 mm (38°) Driver's windows	1 mm (1-8°) Doors 4 mm (1-8°) Windows	1 mm (1-8°) Cabin 4 mm (86°) Rear cover	4 mm
Launcher	5 mm (10°)	5 mm	5 mm (10°)

Notes:

• Wheels are 10 mm thick.
• No armour in front grille, simple 7.62 mm machine gun rounds can enter and damage the engine.

 Mobility

 

Controlled suspension

It is possible to adjust the ground clearance or more complex suspension positions

Speedforward / back

AB79 / 11 km/h

RB and SB73 / 10 km/h

Number of gears5 forward

1 back

Weight6.4 t

Engine power

AB181 hp

RB and SB95 hp

Power-to-weight ratio

AB28.3 hp/t

RB and SB14.8 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	79	11	6.4	134	181	20.94	28.28
Realistic	73	10		84	95	13.13	14.84

Being a wheeled vehicle with a rather high ground pressure, the BM-31-12 has issues traversing soft and uneven terrain (sand, snow, mud, hills), as expected from a truck. On hard terrain (roads, concrete, etc.), it can reach 72 km/h but the acceleration to get to those speeds is poor. The brakes are not powerful so you'll have to anticipate the braking phases to stop in time. The turn radius is also quite large: you won't be able to change directions easily

 Modifications and economy

Repair cost

AB1 761

RB2 092

SB1 524

Crew training10 000

Experts67 000

Aces330

Research Aces570 000

Reward for battleAB / RB / SB

2 × 90 / 140 / 150 %

2 × 136 / 136 / 136 %

Modifications

Mobility	Protection	Firepower
Tires Suspension Brake System Filters Transmission Engine	Improved Parts Improved FPE Crew Replenishment	Horizontal Drive Elevation Mechanism Artillery Support

 Armaments

 Main armament

300 mm M-31 rocket

Ammunition12 rounds

Reloadbasic crew → aces

10.4 → 8.0 s

Vertical guidance10° / 48°

Horizontal guidance-10° / 10°

Flight speed245 m/s

Range4 000 m

300 mm M31-UK rockets					Turret rotation speed (°/s)					Reloading rate (seconds)
Mode	Capacity	Vertical	Horizontal	Stabilizer	Stock	Upgraded	Full	Expert	Aced	Stock	Full	Expert	Aced
Arcade	12	+10°/+48°	±10°	N/A	6.2	8.5	10.4	11.5	12.2	10.40	9.20	8.48	8.00
Realistic					4.2	4.9	6.0	6.6	7.0

 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

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%

Ammo racks

Ammo racks and firing order of BM-31-12

Full ammo	Visual discrepancy
12	No

Notes:

• Rockets deplete inwards, starting from the outside-left rocket on the top row. Rockets then deplete outwards, starting with the inner left rocket on the bottom row. See attached image.

 Usage in battles

There are two main ways to use the Andryusha, which are very similar in playstyle to its smaller sibling, the Katyusha

Artillery

Usage of this vehicle in its intended role of rear-line support and artillery strike. One should estimate the correct angle, shoot a rocket, watch where it lands, adjust fire, and retry it as needed. Do not take too much time with this method of rangefinding since a single retaliatory shot can end your day. Once the correct sight distance is found, unleash hell on your enemies, blinding them with dust lifting up from the ground, detonating ammo racks and blasting off tracks. This is basically an intelligent artillery barrage. Once all rockets are fired, fall back behind allied lines, find a captured objective to reload at, and repeat. Keep in mind that firing the M-31-UK rocket have a very loud launch noise, and will alert enemies all around to your presence.

There is little the Andryusha can do against enemy aircraft, which can kill the vehicle with as little as a half-second machine gun burst or a relatively close detonation of a bomb or rocket. Try not to get caught out in the open, and try to hide behind obstacles. Its always recommended to have friendly cover while playing this vehicle.

Ambusher

Best used in an urban or dense maps, where enemies usually will rush down a path or corridor quickly without checking all of their sorroundings. Find yourself a pile of rubble or other kind of short cover and lower the front suspension of the truck in such a way that you can fire right in front of you just past the obstacle. When an enemy passes by, simply hit it with a rocket. This tactic is often a last resort when you're cornered and encircled. You may kill one or more enemies if you're lucky, but you will eventually be caught or your rockets will run out.

 Pros and cons

Pros:

• Very powerful 300 mm rockets with a high explosive mass. Able to take out almost all vehicles in a single direct hit
• Adjustable suspension
• Can be used in deceptions: a similar model is used as a static decoration on some maps, with a different launcher and with the armor plates lifted. This may allow the player to hide in plain sight. Works better when in groups of 2 Andryushas or more, and especially if someone in your squad has the Katyusha
• Launcher sight helps with aiming to play as an indirect fire weapon

Cons:

• Very poor survivability
• Has issues traversing rough and muddy terrains, to be expected from a wheeled vehicle
• Poor horizontal launcher traverse
• Low ammunition supply of 12 rockets
• Loud and distinguishable firing sound
• Lacks other armaments beside rockets
• Large dead zone in front of vehicle up to 250 m (launcher depression of +10°)
• Vehicle cannot move properly while suspension is adjusted
• In RB & SB, cannot reload unless on allied capture point and can only reload one rocket at a time; can sometimes take around 2 minutes to completely reload its rockets

 History

Describe the history of the creation and combat usage of the vehicle in more detail than in the introduction. If the historical reference turns out to be too long, take it to a separate article, taking a link to the article about the vehicle and adding a block "/History" (example: https://wiki.warthunder.com/(Vehicle-name)/History) and add a link to it here using the main template. Be sure to reference text and sources by using <ref></ref>, as well as adding them at the end of the article with <references />. This section may also include the vehicle's dev blog entry (if applicable) and the in-game encyclopedia description (under === In-game description ===, also if applicable).

 Media

Excellent additions to the article would be video guides, screenshots from the game, and photos.

 See also

Other vehicles of similar configuration and role

• BM-13N
• BM-8-24

 External links

• [Event] Legend of Victory: BM-31-12 “Andryusha”
• [Devblog] BM-31-21: Katyusha's Little Brother