The M68 is an American 105 mmtank gun. It uses a British-designed L7 gun tube and cartridges with an American-designed mount, breech assembly and recoil mechanism.
M68
Front view of a M68E1 gun on an American M60A3 main battle tank during a military exercise in Nuremberg, 1986.
The M68 uses a concentric recoil spring instead of a separate buffer and recuperator hydraulic cylinders.
The M68 has a cylindrical breech with a vertical sliding breech block instead of a square-shaped breech with a horizontal sliding breech block.[1]
Firing is electrical only.
The M68 barrel is secured to the breech by a tapered pin and interrupted breech threads which allow the barrel to be removed from the gun shield without having to dismantle the mantlet.[2]
The M68 is fitted with an eccentric bore evacuator instead of a concentric model in order to provide more clearance over the rear deck.
The M68 chamber has a difference in the length of its shoulder, producing a different diametral taper near the freebore.
Models
M68 : initial production variant, used on the original variant of the M60 tank and the M116 gun mount.[3] Retrofitted to the M48A5.
M68E1 : variant used on the M60A1 and M60A3 tanks in mount M140. They were fitted with a fiberglassthermal shroud[4] in 1973.
M68A1 : improved variant built in 1980[5] for use on the M1 and IPM1 versions of the M1 Abrams.[6][7] The M68A1 features an aluminium thermal shroud and a pad for fixing the muzzle reference sensor.
M68A1E4 : a light weight, low-recoil version of the M68A1 designed for the M1128 Mobile Gun System (Stryker MGS). Also designated as M68A2, it features an Ares Incorporated long stroke, low recoil impulse mechanism and a muzzle brake (later removed).[8] The breech is mounted upside down to accommodate the automatic loader.
Foreign variants
KM68A1 : licence-produced variant of the US M68A1 gun for the South Korean Army. Used on the South Korean variant of the M48, the M48A5K and K1 tanks.
M68T : Turkish licence-built versions by MKEK under the designation of M68T to up-gun its 90 mm armed M48 fleet, took place in the 1980s.
M64 L71A : Israeli variant built by IMI for the Merkava Mk. I and Mk. 2 tanks.
Prototypes
T254E1 : US designation for the L7A1, it had the same horizontal sliding breech block as the L7 and used British X15/L52 barrels with a concentric bore evacuator on the barrel.
T254E2 : US variant of the T254, it had a vertical drop breech block with the X15E8 barrel and a concentric bore evacuator. Later standardized as M68. Used in M60 Patton prototype vehicles.
T254E3 : US variant designed in 1975, identical to thee T254E2/M68 but with chrome-plated bores. Only two built.[9][10]
XM24 : the XM24[11] gun tube was extended by 1.5 m (4 ft 11 in) compared to the M68A1 and it could tolerate a higher chamber pressure. Designed to replace the 105mm gun M68A1 in the M1 and the IPM1, it was expected to have improved penetration performance, particularly with the upcoming XM900 APFSDS (later cancelled and superseeded by the M900A1). At that time, it was expected that the installation of the enhanced 105 mm gun would be less costly than retrofitting the M1 and IPM1 with the 120 mm gun M256. The program was initiated in March 1983, the Watervliet Arsenal manufactured 14 XM24 tubes and 17 breeches for cannon during the fiscal year 1984.[12] The US Army completed the advanced development phase in February 1984 and initiated it for the M1 in March. Full-scale development was expected to begin in November 1984 for the M60A3 and in January 1985 for the Abrams but the program was abandoned.[13]
Usage
M1 Abrams: M68A1 cannon used early production models (M1 and IPM1)
^Conners, Chris. "105mm Gun Tank M60". afvdb.50megs.com. Retrieved 19 August 2022.
^Foss, Christopher (1993). Jane's Armoured Fighting Vehicle Retrofit Systems 1993-94. London: Jane's Information Group. p. 41. ISBN978-0710610799.
^Direct Support, General Support, and Depot Maintenance Manual for Cannon, 105-MM Gun, M68 & M68E1, M116 and 140.TM 9-1000-213-35 by Fred C. (Chief of Staff) Weyand Jan 1, 1978
^Hunnicutt, R.P. (2015). Patton: A History of the American Main Battle Tank. Echo Point Books & Media. p. 443. ISBN978-1626548794.
^Cannon, 105mm Gun: M68A1E2 MIL-C-45504A Rev. D Jan 1987 Military and Government Specs & Standards (Naval Publications and Form Center) (NPFC)
^Hunnicutt, R.P. (1990). Abrams: A History of the American Main Battle Tank. Presidio. p. 312. ISBN9780891413882.
^M1 Abrams in Action By Jim Mesko – 1996 Squadron/Signal publications
^"Army Programs - Stryker - Mobile Gun System (MGS)" (PDF). DOT&E. p. 83.
^Hunnicutt, R. P. Patton: A History of the American Main Battle Tank. 1984; Presidio Press. ISBN0-89141-230-1 p.119
^"Data" (PDF). apps.dtic.mil. (PDF) from the original on December 1, 2020. Retrieved 2020-04-11.
^"M60A3 Patton Tank Thermal Sight (TTS)". www.globalsecurity.org.
^"M60A3 Patton Tank Thermal Sight (TTS)". globalsecurity.org. Retrieved 19 August 2022.
^Hunnicutt, R.P. (1990). Abrams: A History of the American Main Battle Tank. Presidio. p. 202. ISBN9780891413882.
^"M60 Patton Series - Globalsecurity.org". from the original on 2008-12-02. Retrieved 2008-12-02.
January 09, 2023
tank, american, tank, uses, british, designed, tube, cartridges, with, american, designed, mount, breech, assembly, recoil, mechanism, m68front, view, m68e1, american, m60a3, main, battle, tank, during, military, exercise, nuremberg, 1986, typetank, gunplace, . The M68 is an American 105 mm tank gun It uses a British designed L7 gun tube and cartridges with an American designed mount breech assembly and recoil mechanism M68Front view of a M68E1 gun on an American M60A3 main battle tank during a military exercise in Nuremberg 1986 TypeTank gunPlace of originUnited StatesUnited KingdomService historyIn service1960 presentProduction historyDesignerWatervliet ArsenalManufacturerWatervliet ArsenalProduced1959 presentVariantsM68E1 M68A1 M68A1E4SpecificationsMass754 kg 1 662 lb gun tube 1 128 kg 2 487 lb recoiling gun mass Length5 550 mm 218 50 in overall Barrel length5 347 mm 210 51 in gun tube Shell105 617mm RCalibre105 mm 4 134 in Breechsemi automatic vertical sliding breechblockRecoil305 mm Contents 1 Technical characteristics 2 Models 2 1 Foreign variants 2 2 Prototypes 3 Usage 4 See also 5 ReferencesTechnical characteristics EditThe M68 differs from the L7 in several aspects The M68 uses a concentric recoil spring instead of a separate buffer and recuperator hydraulic cylinders The M68 has a cylindrical breech with a vertical sliding breech block instead of a square shaped breech with a horizontal sliding breech block 1 Firing is electrical only The M68 barrel is secured to the breech by a tapered pin and interrupted breech threads which allow the barrel to be removed from the gun shield without having to dismantle the mantlet 2 The M68 is fitted with an eccentric bore evacuator instead of a concentric model in order to provide more clearance over the rear deck The M68 chamber has a difference in the length of its shoulder producing a different diametral taper near the freebore Models EditM68 initial production variant used on the original variant of the M60 tank and the M116 gun mount 3 Retrofitted to the M48A5 M68E1 variant used on the M60A1 and M60A3 tanks in mount M140 They were fitted with a fiberglass thermal shroud 4 in 1973 M68A1 improved variant built in 1980 5 for use on the M1 and IPM1 versions of the M1 Abrams 6 7 The M68A1 features an aluminium thermal shroud and a pad for fixing the muzzle reference sensor M68A1E4 a light weight low recoil version of the M68A1 designed for the M1128 Mobile Gun System Stryker MGS Also designated as M68A2 it features an Ares Incorporated long stroke low recoil impulse mechanism and a muzzle brake later removed 8 The breech is mounted upside down to accommodate the automatic loader Foreign variants Edit KM68A1 licence produced variant of the US M68A1 gun for the South Korean Army Used on the South Korean variant of the M48 the M48A5K and K1 tanks M68T Turkish licence built versions by MKEK under the designation of M68T to up gun its 90 mm armed M48 fleet took place in the 1980s M64 L71A Israeli variant built by IMI for the Merkava Mk I and Mk 2 tanks Prototypes Edit T254E1 US designation for the L7A1 it had the same horizontal sliding breech block as the L7 and used British X15 L52 barrels with a concentric bore evacuator on the barrel T254E2 US variant of the T254 it had a vertical drop breech block with the X15E8 barrel and a concentric bore evacuator Later standardized as M68 Used in M60 Patton prototype vehicles T254E3 US variant designed in 1975 identical to thee T254E2 M68 but with chrome plated bores Only two built 9 10 XM24 the XM24 11 gun tube was extended by 1 5 m 4 ft 11 in compared to the M68A1 and it could tolerate a higher chamber pressure Designed to replace the 105mm gun M68A1 in the M1 and the IPM1 it was expected to have improved penetration performance particularly with the upcoming XM900 APFSDS later cancelled and superseeded by the M900A1 At that time it was expected that the installation of the enhanced 105 mm gun would be less costly than retrofitting the M1 and IPM1 with the 120 mm gun M256 The program was initiated in March 1983 the Watervliet Arsenal manufactured 14 XM24 tubes and 17 breeches for cannon during the fiscal year 1984 12 The US Army completed the advanced development phase in February 1984 and initiated it for the M1 in March Full scale development was expected to begin in November 1984 for the M60A3 and in January 1985 for the Abrams but the program was abandoned 13 Usage EditM1 Abrams M68A1 cannon used early production models M1 and IPM1 M47 Patton in some upgraded variants M47M Iranian modification of US supplied M47Ms Sabalan Iranian modification Tiam Iranian modification M48 Patton in some upgraded variants M48A5 US model Magach 3 Israeli modification CM 11 Brave Tiger Taiwanese modification CM 12 Tank Taiwanese modification M48A5K1 South Korean modification M48A5T1 Turkish modification M60 tank M60 and M60A1 using M68 M60A3 using M68E1 14 M1128 Mobile Gun System M68A1E4 cannon Expeditionary tank K1 Type 88 KM68A1 cannon Merkava Mark I and Mark II models T 54 55 in some upgraded variants Tiran 4Sh Israeli modification of T 54 both L7 and M68 variants fitted Tiran 5Sh Israeli modification of T 55 both L7 and M68 variants fitted Type 72Z Iranian modernization of T 54 55 and Type 59 Ramses II Egyptian modernization of T 55See also EditCN105 F1 French counterpart L7 British counterpart D 10T Russian counterpart U 5TS Russian counterpart References Edit Conners Chris 105mm Gun Tank M60 afvdb 50megs com Retrieved 19 August 2022 Foss Christopher 1993 Jane s Armoured Fighting Vehicle Retrofit Systems 1993 94 London Jane s Information Group p 41 ISBN 978 0710610799 Direct Support General Support and Depot Maintenance Manual for Cannon 105 MM Gun M68 amp M68E1 M116 and 140 TM 9 1000 213 35 by Fred C Chief of Staff Weyand Jan 1 1978 Hunnicutt R P 2015 Patton A History of the American Main Battle Tank Echo Point Books amp Media p 443 ISBN 978 1626548794 Cannon 105mm Gun M68A1E2 MIL C 45504A Rev D Jan 1987 Military and Government Specs amp Standards Naval Publications and Form Center NPFC Hunnicutt R P 1990 Abrams A History of the American Main Battle Tank Presidio p 312 ISBN 9780891413882 M1 Abrams in Action By Jim Mesko 1996 Squadron Signal publications Army Programs Stryker Mobile Gun System MGS PDF DOT amp E p 83 Hunnicutt R P Patton A History of the American Main Battle Tank 1984 Presidio Press ISBN 0 89141 230 1 p 119 Data PDF apps dtic mil Archived PDF from the original on December 1 2020 Retrieved 2020 04 11 M60A3 Patton Tank Thermal Sight TTS www globalsecurity org M60A3 Patton Tank Thermal Sight TTS globalsecurity org Retrieved 19 August 2022 Hunnicutt R P 1990 Abrams A History of the American Main Battle Tank Presidio p 202 ISBN 9780891413882 M60 Patton Series Globalsecurity org Archived from the original on 2008 12 02 Retrieved 2008 12 02 Retrieved from https en wikipedia org w index php title M68 tank gun amp oldid 1132017898, wikipedia, wiki, book, books, library,
