45 mm/68 21-KM (45 mm)

A pair of 21-KM semi-automatic cannons on Baku

Description

The 45 mm/68 21-KM is an upgraded variant of the 45 mm/46 21-K with a longer barrel and thus higher muzzle velocity.

Vehicles equipped with this weapon

• BMO
• MBK-161 late
• MO-4

General info

Tell us about the tactical and technical characteristics of the cannon or machine gun.

Available ammunition

Describe the shells that are available for the weapon and their features and purpose. If it concerns autocannons or machine guns, write about different ammo belts and what is inside (which types of shells).

Comparison with analogues

Give a comparative description of cannons/machine guns that have firepower equal to this weapon.

Usage in battles

Describe the cannon/machine gun in the game - its distinctive features, tactics of usage against notable opponents. Please don't write a "guide" - do not impose a single point of view, but give the reader food for thought.

Pros and cons

Summarise and briefly evaluate the weaponry in terms of its characteristics and combat effectiveness. Mark pros and cons as a list.

Pros:

Cons:

History

The 21-KM's story begins in 1926 with a 37 mm anti-tank gun prototype made by Rheinmetall. The Soviet Union, needing an anti-tank gun but lacking the know-how to make one, turned to Germany and the two nations agreed in secret to have German companies develop Soviet artillery designs to bypass the armament restrictions of the Treaty of Versailles. The result was the 37 mm anti-tank gun M1930 (1-K), the Soviet Union's first dedicated anti-tank weapon and an early proof of concept of what would become the PaK L/45. Shortly after the 1-K began production in the Soviet Union in March of 1932, V. Bering at Factory No. 8 created the 19-K 45 mm anti-tank gun M1932 which scaled up the gun barrel to 45 mm for the economical reason that the Soviets had it in stock. The 19-K would be developed into the 21-K as an anti-aircraft weapon for the Soviet Navy, but the gun would be superseded by the automatic 70-K as the main naval anti-aircraft gun in 1942. The production of the 21-K however continued and that same year the No. 172 Plant in Motovilikha made the 45 mm anti-tank gun M1942 (M-42) for the Red Army which was effectively a longer barrelled variant of the 19-K. The variant was also adopted by the Soviet Navy as the 21-KM and by this point, production completely switched to monobloc barrels from the original built-up gun barrels. Production ended in 1947 just like the 21-K itself.

Media

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

See also

• 45 mm/46 21-K (45 mm): Original naval cannon
• 45 mm 20-K (45 mm): Tank variant

External links

Paste links to sources and external resources, such as:

• topic on the official game forum;
• other literature.

USSR naval cannons
20 mm	ShVAK
25 mm	2M-3
30 mm	AK-230 · 30 mm/54 AK-630 · 30 mm/54 AK-630M · BP "Plamya"
37 mm	37 mm/67 70-K · V-11
45 mm	45 mm/46 21-K · 45 mm/68 21-KM · 45 mm/89 SM-20-ZIF · 45 mm/89 SM-21-ZIF
57 mm	AK-725
75 mm	75 mm/50 Canet patt.1892
76 mm	34-K · 39-K · 76 mm/60 AK-176M · AK-726 · D-56TS · F-34 · Lender AA gun, pattern 1914/15
85 mm	85 mm/52 92-K · 85 mm/54.6 ZIS-C-53 · 90-K
100 mm	100 mm/56 B-34 · 100 mm/70 SM-5-1 · Minizini
102 mm	Pattern 1911
120 mm	120 mm/50 pattern 1905
130 mm	130 mm/55 pattern 1913 · 130 mm/58 SM-2-1 · B-13
152 mm	152 mm/57 B-38
180 mm	180 mm/57 B-1-P · 180 mm/60 B-1-K
305 mm	12-inch/52 pattern 1907 · 305 mm/54 B-50
356 mm	14-inch/52 pattern 1913 (356 mm)
	Foreign:
40 mm	2pdr QF Mk.IIc (Britain) · Skoda (Czechoslovakia)
47 mm	3 pdr QF Hotchkiss (Britain)
76 mm	76 mm/40 Ansaldo mod.1917 (Italy)
88 mm	SK C/30 (Germany)
120 mm	120 mm/50 Mk.4 Bofors M1924 (Sweden) · 120 mm/50 O.T.O. Mod.1933 (Italy)
152 mm	152/53 mm O.T.O. Mod.1929 (Italy)
320 mm	320 mm/44 Ansaldo model 1934 (Italy)