37mm AND 57mm AUTOMATIC ANTIAIRCRAFT GUNS

37mm automatic antiaircraft gun M1939
37mm automatic antiaircraft gun M1939 (twin)
57mm automatic antiaircraft gun S-60
57mm automatic antiaircraft gun (Czechoslovak model)

The Soviet recoil-operated 37mm antiaircraft guns are based on a Bofors design and closely resemble the 40mm guns used in both the British and United States forces during World War II. Although the single mount is the most common version, a twin mount was produced and has been exported to Algeria. The Soviet Navy also employs a twin water-cooled version closely reselling the multi-mount United States 40mm guns used in World War II. The Soviet 37mm guns have hydraulic recoil buffers and spring recunerators. The breechblocks are of the rising block type. The field mobile weapon may be equipped with a shield. There is no provision for radar fire control.

The 57mm S-60 gun is a recoil-operated weapon which has replaced the earlier 37mm models in most Warsaw Pact units. It is a powerful weapon, well suited to attack armored vehicles as well as low-flying aircraft. In addition to on-carriage optical fire control, the S-60 also employs off-carriage fire control with the PUAZO-6/60 director and the SON-9 or SON-9A radars. Originally the PUAZO-5 director and SON-4 radar were used. Further improved director/radar combinations have also become available in recent years.

Recognition features of the S-60 are the long, thin tube with multi-perforated nuzzle brake, distinctive gun shield which folds down and the horizontal feed tray which holds the four-round clips. The normal Soviet prime mover is the Ural-375 truck. A twin version, the S-68, is mounted on the self-propelled ZSU-57-2, and twin and quad versions are used by tie Soviet Navy. It should be noted that the ammunition for the 57mm antiaircraft guns is not interchangeable with that used by the 57mm antitank and assault guns. This is due to the different configuration and dimensions of the cartridge cases.

Both the 37mm gun M1939 and 57mm' gun S-60 are used in Communist China where they are known as the Type 55 and Type 59 respectively.

In addition to these weapons, a distinctive 57mm automatic gun was produced in Czechoslovakia and is still used in some units in that country. It can be distinguished by the absence of a muzzle brake, the distinctive shield and the placing of the recoil system both above and below the tube.

37mm AND 57mm AUTOMATIC ANTI-AIRCRAFT GUNS		M1939	S-60	Czech
Caliber	mm	37	57	57
Length of tube in cals		66.7	71
Length of tube overall	mm	2729	4390	4000
Weight in firing position	kg	2100*	4500	5150
Weiqht in travel position	kg	2100*	4600
Length in travel position	mm	6036	8500	5500
Width in travel position	mm	1937*	2054
Height in travel position	mm	2105*	2370	2000
Track	mm	1545	1935
Clearance	mm	360	380
Tire size		6.50x20	34x7
Height of axis of bore 0°	mm	1100	1300
Elevation	°	+85	+85	+87
Depression	°	-5	-4	-5
Traverse	°	360	360	360
Rate of fire per tube:
cyclic	rpm	160-180	105-120	80-90
practical	rpm	80	70
Feed		5-rd clip	4-rd clip	3-rd clip
Projectile weight:  HE	kg	0.73	2.8	2.58
APHE	kg	0.76	3.1	3.1
HVAP	kg	0.62	---	---
Muzzle velocity:    HE	m.s	880	1000	1005
APHE	m.s	880	1000	1005
HVAP	m.s	960	---	---
Maxi muni-range:  horizontal	m	9500	12000	12000
vertical	m	6700	8800	8800
Effective AA range
Off-carriage control	m	---	6000	6000
On-carriage control	m	3000	4000	4000
Pointblank range:       APHE			1100	1100
2m high target  HVAP			---	---
Armor penetration:     APHE'	mm	46	106	106
0°/500nm         HVAP	mm		---	---
Crew		8	7	7
Unit of fire	rds	200	200	200
*without shield, shield weighs 100 kg