L-11 76.2 mm tank gun

L-11 76.2 mm tank gun
T-34 Model 1940 with L-11 gun
Type	Tank gun
Place of origin	Soviet Union
Service history
Used by	Soviet Union  Nazi Germany
Wars	World War II
Production history
Designer	IA Makhanov
Designed	1938
Manufacturer	Kirov Plant
Produced	1939-1941
Variants	L-17
Specifications
Barrel length	2.3 m (7 ft 7 in) L/30.5[1]
Shell	Fixed QF 76.2 × 385 mm. R
Shell weight	6.5 kg (14 lb 5 oz)
Caliber	76.2 mm (3.00 in)[1]
Breech	Semi-automatic vertical sliding-wedge
Recoil	Hydro-pneumatic
Elevation	2° to 25°
Traverse	360°[2]
Rate of fire	6-7 rpm
Muzzle velocity	613 m/s (2,010 ft/s)
Maximum firing range	5.6 km (3.5 mi)[2]

7.62 cm FK 250(r)
Type	Field gun
Place of origin	Soviet Union
Service history
Used by	Soviet Union  Nazi Germany
Wars	World War II
Production history
Designer	Kirov Plant
Produced	1941-1942
Specifications
Mass	1,325 kg (2,921 lb)
Barrel length	2.3 m (7 ft 7 in) L/30.5[1]
Shell	Fixed QF 76.2 × 385 mm. R
Shell weight	6.5 kg (14 lb 5 oz)
Caliber	76.2 mm (3.00 in)[1]
Breech	Semi-automatic vertical sliding-wedge
Recoil	Hydro-pneumatic
Carriage	Split-trail
Elevation	-5° to +37°
Traverse	55°[1]
Rate of fire	6-7 rpm
Muzzle velocity	613 m/s (2,010 ft/s)
Maximum firing range	5.6 km (3.5 mi)[1]

The L-11 76.2 mm tank gun was a Soviet tank gun, used on the earliest models of the T-34 Model 1940 medium tank and KV-1 Model 1939 heavy tank during World War II.

History

The L-11 was designed in 1938 by IA Makhanov of the SKB-4 design bureau at the Kirov Plant in Leningrad. It was 30.5 calibers long,^[3] had a semi-automatic vertical sliding-wedge breech, used fixed quick-fire 76.2 x 385 mm R ammunition and had a hydro-pneumatic recoil mechanism.

It has been claimed that the L-11 was based on the 76 mm air-defense gun M1914/15 designed by VV Tarnovsky and F. F. Lender.^[4] What can be said is that both the M1914/15 and L-11 had similar lengths, similar muzzle velocities (592 m/s vs 613 m/s), were built in the same factory and fired the same ammunition.

Through a combination of administrative interference by Marshal Grigory Kulik and bureaucratic inertia, the first models of the T-34 and KV-1 were both armed with the L-11. Testing of both tanks highlighted an undesirable situation where both a medium tank and heavy tank were equal in firepower and neither had the firepower necessary to defeat a foreign tank of similar capabilities. Although an acceptable tank gun by the standards of the time the L-11 did not have a substantial performance advantage over foreign designs. Therefore, the L-11 was a stopgap until improved guns for the T-34 and KV-1 could be produced. An early favorite to replace the L-11 was a modified version of the 76 mm air defense gun M1931, but delays and difficulties saw it passed over despite excellent performance.^[4]

During 1941 the L-11 was replaced on T-34 production lines by the 42.5 caliber F-34 and on KV-1 production lines by the 31.5 caliber F-32. Despite being considered a superior design the performance of the F-32 gun was not substantially better than the L-11 and inferior to the F-34 gun used on the T-34. Eventually, the F-32 gun was replaced on the KV-1 production lines by a modified version of the F-34 gun called the ZiS-5, finally giving the T-34 and KV-1 parity in firepower.^[4]

Variants

L-17 casemate gun

During the 1930s the Red Army proposed creation of a new 76 mm casemate gun capable of withstanding a direct hit from a 76 mm armor-piercing projectile fired from a distance of 400 m (1,300 ft) or the explosion of a 203 mm (8.0 in) high-explosive projectile at a distance of 1 m (3 ft 3 in) from the pillbox.

The design bureau of the Kirov Plant under the leadership of IA Makhanov responded by creating a variant of the L-11 which it called the L-17. The L-17 was mounted in a heavily armored gun mantlet with the barrel inside of an armored tube. In May 1939, the Kirov plant received an order for six-hundred L-17 guns. During testing between September 29 and October 8, 1939 the L-17 withstood the impact of a 76 mm armor piercing projectile fired from a M1902/30 field gun at a velocity of 529–547 m (1,736–1,795 ft) at a distance of 50 m (160 ft). The first L-17's were installed in June 1940 in the Kamenets-Podilsky fortified area.^[5]

Field gun conversion

During 1941-1942 a field gun based on the L-11 was introduced. It consisted of an L-11 barrel on the split-trail carriage used by the ZiS-3. This adaptation was probably done to address the huge losses of artillery suffered during the summer of 1941 and to use surplus L-11 barrels. The Soviet designation for this gun is not known, but the Germans referred to them as the 7.62 cm FK 250(r).^[1]

Comparison of guns

Notes

References

• Chamberlain, Peter. Gander Terry. 1975. Light and medium field artillery. New York: Arco. ISBN 0668038209.
• Zaloga, Steve. 1994. T-34/76 Medium Tank 1941-45. Osprey Publishing. ISBN 978-1-85532-382-7
• Zaloga, Steve. Grandsen, James. 1984. Soviet tanks and combat vehicles of World War Two. London: Arms and Armour Press. p225. ISBN 0853686068.

External links

• http://www.armchairgeneral.com/rkkaww2/weapons/art_tanks.htm
• http://tankarchives.blogspot.com/2016/02/minor-modernization-t-150.html
• http://www.plam.ru/tehnauka/genii_sovetskoi_artillerii_triumf_i_tragedija_v_grabina/p15.php