20-K (45 mm)

Description

The 20-K (45mm) is equipped on a number of rank 1 Russian tanks. It is a decent gun for its rank, and still is useful in up-tiers due to its high-penetrating APCR shell.

Vehicles equipped with this weapon

Vehicles equipped with this weapon
Light tanks
BT-5	BT-5 · RBT-5
BT-7	BT-7
T-26	T-26 · T-26 (1st Gv.T.Br.) · ␗T-26 · T-26 No.531 · T-26E
Other	BA-11 · T-50 · T-70 · T-80 · T-126
Heavy tanks	SMK · T-35

General info

Available 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
BR-240	APHEBC	69	68	59	50	42	35
BR-240P	APCR	104	99	72	49	33	23
BR-240SP	AP	73	71	62	52	44	37
O-243	HE	4	4	4	4	4	4

Shell details
Ammunition	Type of warhead	Velocity (m/s)	Projectile Mass (kg)	Fuse delay (m)	Fuse sensitivity (mm)	Explosive Mass (TNT equivalent) (g)	Normalisation at 30° from horizontal	Ricochet
								0%	50%	100%
BR-240	APHEBC	760	1.43	1.2	9.0	29.3	+4.0°	48°	63°	71°
BR-240P	APCR	1,070	0.85	N/A	N/A	N/A	+1.5°	66°	70°	72°
BR-240SP	AP	757	1.43	N/A	N/A	N/A	-1.0°	47°	60°	65°
O-243	HE	343	2.15	0.4	0.3	118	0.0°	79°	80°	81°

Shell types:

• BR-240: APHEBC - This should be the main ammo type that you use, as it deals the most damage because of its explosive filler.
• BR-240P: APCR - This shell should only be used against more heavily armoured targets that the BR-240 cannot penetrate.
• BR-240SP: AP- It is recommended to avoid this kind of shell as it is inferior in most aspects compared to the BR-240P ammo.
• O-243: HE - Carry only very few of these. They are useless against anything other than unarmored AA vehicles.

Comparison with analogues:

Germany - 50 mm KwK 38

USA - 37 mm M6

Great Britain - 57 mm OQF 6-pounder Mk.III

Usage in battles

The 20-K (45mm) is a decent gun for its rank. In down-tiers, it is a very effective and lethal weapon, and can take out most tanks with 1~2 shots. However, in up-tiers, it will be more difficult to take out tanks because of the relatively small caliber. However, this doesn't mean that you are useless. The APCR round is capable of penetrating most rank II vehicles, however, the post-penetration damage is poor due to the lack of an explosive filler.

Pros and cons

Pros:

• Decent penetration
• Quick reload
• Has access to APCR with 104mm of penetration at point-blank
• Shells have a medium-high velocity, makes aiming easier

Cons:

• Due to the small caliber, post-penetration effects are bad
• APHEBC rounds will have trouble

History

The 20-K (45mm) was installed in tanks under the name 45 mm tank gun model 1932 (20-K). In 1934, the gun was improved with a semi-automatic breech instead of the original quarter-automatic version. Other changes were in the elevation mechanism and the recoil system. It was used on a wide variety of Soviet tanks and fired the same ammunition as the anti-tank version. The gun was later improved into the 45 mm tank gun model 1938, which had an electric firing system and a TOS stabilized (in vertical plane only) gun sight, allowing for accurate fire while the tank was in motion. The gyro stabilizer was removed from the design in 1941 due to inexperienced tank crews not activating the stabilizer. During 1941-42, some surplus M1938 barrels were fitted to trailer carriages to replace the losses of anti-tank guns suffered in the opening stages of Operation Barbarrosa. Although the Russian designation for these guns is not known, the Germans gave captured guns the designation 4.5 cm Pak 184/6(r).

Media

An excellent addition to the article would be a video guide, as well as screenshots from the game and photos.

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 article about the variant of the cannon/machine gun;
• references to approximate analogues by other nations and research trees.

External links

Paste links to sources and external resources, such as:

• topic on the official game forum;
• encyclopedia page on the weapon;
• other literature.

China tank cannons
30 mm	ZPL02 · ZPZ02
73 mm	Type 86
76 mm	M32K1
85 mm	Type 56 · Type 63
100 mm	PTP86 · Type 59 · Type 69 · Type 69-II · ZPL04
105 mm	88B-105T · Type 83 · WMA301 · ZPL94 · ZPL98A
120 mm	122TM · PTZ89
125 mm	Type 88C · Type 99A · ZPT98
130 mm	PL59A Gai
152 mm	PL66 Gai
	Foreign:
20 mm	KwK30 (Germany)
37 mm	M6 (USA)
45 mm	20-K (USSR)
47 mm	Type 1 (Japan)
57 mm	Type 97 (Japan) · ZIS-2 (USSR)
75 mm	M2 Howitzer (USA) · M3 (USA) · M6 (USA)
76 mm	D-56T (USSR) · F-34 (USSR) · M1 (USA) · M7 (USA) · ZIS-3 (USSR)
85 mm	ZIS-S-53 (USSR)
90 mm	M3 (USA) · M41 (USA)
100 mm	D-10S (USSR)
105 mm	M68 (USA) · M68A1 (USA)
115 mm	U-5TS (USSR)
122 mm	A-19 (USSR) · D-25T (USSR)
152 mm	ML-20S (USSR)