M68 (105 mm)

This page is about the American tank cannon M68 (105 mm). For other versions, see M68A1 (105 mm) and M68A1E8 (105 mm).

The 105 mm M68 on the M60 gun mantlet.

Description

The 105 mm M68 is an American tank cannon that saw widespread use among American armoured fighting vehicles during the Cold War. Based off the British 105 mm L7 gun, the 105 mm M68 shares many characteristics as the British counterpart such as the access to the HESH (High-Explosive Squash-Head) ammunition.

As the main armament of the many M60 variants and the early M1 Abrams tanks, players will become intimately familiar with the 105 mm M68 gun whether from the firing or receiving end of the tanks.

General info

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

Available ammunition

Not all ammunition listed is available on all vehicles equipped with this weapon.

American 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
M456	HEATFS	400	400	400	400	400	400
M456A2	HEATFS	400	400	400	400	400	400
M393A2	HESH	127	127	127	127	127	127
M392A2	APDS	350	347	333	317	302	287
M728	APDS	265	263	252	240	228	216
M735	APFSDS	292	291	284	275	266	257
M774	APFSDS	372	370	365	358	351	343

Shell details
Ammunition	Type of warhead	Velocity (m/s)	Projectile mass (kg)	Fuse delay (m)	Fuse sensitivity (mm)	Explosive mass (TNT equivalent) (kg)	Ricochet
							0%	50%	100%
M456	HEATFS	1,174	10.5	0.05	0.1	1.27	65°	72°	77°
M456A2	HEATFS	1,174	10.5	0.05	0.1	1.27	65°	72°	77°
M393A2	HESH	732	11.2	0.1	4	4.31	73°	77°	80°
M392A2	APDS	1,478	4	-	-	-	75°	78°	80°
M728	APDS	1,426	4.53	-	-	-	75°	78°	80°
M735	APFSDS	1,501	3.72	-	-	-	78°	80°	81°
M774	APFSDS	1,509	3.4	-	-	-	78°	80°	81°

Smoke shell characteristics
Ammunition	Velocity (m/s)	Projectile mass (kg)	Screen radius (m)	Screen deploy time (s)	Screen hold time (s)	Explosive mass (TNT equivalent) (g)
M416	732	11.6	16	5	25	50

Israeli 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
M156	HESH	127	127	127	127	127	127
M152	HEATFS	400	400	400	400	400	400

Shell details
Ammunition	Type of warhead	Velocity (m/s)	Projectile mass (kg)	Fuse delay (m)	Fuse sensitivity (mm)	Explosive mass (TNT equivalent) (kg)	Ricochet
							0%	50%	100%
M156	HESH	731	11.4	0.1	4	3.17	73°	77°	80°
M152	HEATFS	1,174	10.5	0.05	0.1	1.27	65°	72°	77°

Comparison with analogues

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Usage in battles

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Pros and cons

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Pros:

Cons:

History

Following the development and experience with the M48 Patton III tank, the United States recognized that the next step towards tank modernization included a greater firepower advantage than the 90 mm calibre used so far since the M26 Pershing tank. As such, when the Ordnance Tank Automotive Command (OTAC) developed the XM60 weapon system on 04 June 1958 to fulfill the US Army's desire for an interim tank prior to the fielding of their ideal main battle tank, a new tank gun was prioritized as one of the upgrades over the M48 tank.

A USMC M60A1 with its 105 mm M68 cannon. The eccentric bore evacuator design can be distinguished, being slightly higher than the gun's bore axis.

Comparative evaluations for a new tank gun began in October 1958, with one highly favorable British 105 mm gun designated the X15E8, which was also referred to as the "Ex 20 pounder" as it was derived from that gun design (and would later be more well known as the L7 gun). The American had developed a version of this gun designated the T254, tested in the T95E5 medium tank, that used the same calibre and ammunition, but the gun tubes were not interchangeable with the X15E8. This was later developed into the T254E2 which made the tube interchangeable with the British gun, though differed with a concentric bore evacuator compared to the British eccentric evacuator (slightly raised above the gun tube) which allowed greater gun depression over the rear engine deck. Another difference in the two guns was that the British breech block moved horizontally, while the American breech block moved vertically. During this development, Ordnance debated whether to move forward with the 105 mm or a lightened 120 mm T123E6 gun based on the M103's 120 mm M58 gun. However, the 105 mm was eventually chosen in accounting for the 120 mm's two-piece ammunition construction restricting the rate of fire. Ultimately, the American T254E2 with the British X15E8's gun tube and eccentric bore evacuator design was chosen as the basis of the XM60's gun. British-made gun tubes would be used until American-manufactured gun tubes could achieve similar accuracy specifications. This 105 mm gun would be standardized as the 105 mm gun M68.

The 105 mm M68 would see field service the same year the XM60 was adopted on 16 March 1959 as the 105 mm gun full-tracked combat tank M60. It was mounted inside the tank via mount M116 in the M60 and mount M140 in subsequent M60A1 and M60A3. When the M48 tanks were upgraded to mount the 105 mm M68, it did so within a modified mount M87 originally for the 90 mm M41 cannon.

Although only intended as an "alternative armament system" due to its immediate availability compared to the upcoming developed weaponry, the 105 mm M68 remained the primary American tank armament for the majority of the Cold War duration due to the technical difficulties and failures of the US Army's Shillelagh gun/launcher systems. The 105 mm M68 stayed with gradual upgrades such as improving the gun tube wear life with additives in the 105 mm propellant charges. The next version of the M68, the M68A1 only differed in minor details and with a mirror for a muzzle reference system. Even when replaced by the 120 mm M256 as the primary tank armament, the M68 and its variants are still used mounted in vehicles in reserve and foreign service, or experimental versions such as the M68A1E8 on the M1128 Mobile Gun System.

Media

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

See also

• L7 (105 mm) (Family)
  • Royal Ordnance L7A1 (105 mm) - The original gun used as the basis of the American design.
  • M68A1 (105 mm) - An improved version of the M68 with additional features installed.

External links

References

Citations

Bibliography

• Albright, Allan A. and Glenn S. Friar. 1975. ADAO15461: Analysis of Wear Data From 105mm M68 Gun Tubes in Field Service. Springfield, VA: National Technical Information Service.
• Conners, Chris. 2021. "105mm Gun Tank M60." American Fighting Vehicle Database. Last modified October 19, 2021. Webpage (Archive).
• Hunnicutt, Richard P. 1984. Patton: A History of the American Main Battle Tank: Volume I. Novato, CA: Presidio Press.
• Hunnicutt, Richard P. 1990. Abrams: A History of the American Main Battle Tank: Volume 2. Novato, CA: Presidio Press.

USA tank cannons
20 mm	M139
25 mm	LW25 · M242
37 mm	M3 · M5 · M6
57 mm	M1
75 mm	M2 · M2 Howitzer · M3 · M6 · M1897A4 · XM274
76 mm	M1 · M7 · M32 · T185E1
90 mm	M3 · M3A1 · M36 · M41 · M54 · T15E1 · T15E2 · T54 · T208E9
105 mm	M4 · M68 · M68A1 · M68A1E8 · T5E1 · T5E2 · T140E2 · T140E3 · XM35
106 mm	M40A1C
120 mm	M58 · M256 · T53
152 mm	M81 · M162 · XM150E5
155 mm	M185 · T7
165 mm	M135
	Foreign:
20 mm	Rh202 (Germany)
57 mm	6pdr OQF Mk.III (Britain) · ZIS-2 (USSR)
105 mm	Sharir (Israel)
120 mm	IMI MG251 (Israel)

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)

Italy tank cannons
20 mm	Breda Mod.35 · Fucile Controcarri S Mod.39
25 mm	Oerlikon KBA B02
37 mm	Vickers-Terni 37/40 mod.18
47 mm	47/32 mod.35 · 47/32 mod.39 · 47/40 mod.38
60 mm	Cannone da 60/70 · OTO HVG
75 mm	75/18 mod.34 · 75/32 mod.37 · 75/34 mod.39 · Ansaldo 75 L/34 · OTO 75/43 mod.40
90 mm	90/53 mod.41 · Cannone da 90/50 M3A1 · Cockerill Mk.3
100 mm	Cannone da 100/17 Mod.1914
105 mm	Cannone Ansaldo da 105/25 · OTO Melara 105/52 · OTO Melara 105/55
106 mm	Cannone da 106 s.r.M40A1
120 mm	OTO Breda 120/44 · OTO Melara 120/45
	Foreign:
30 mm	Bushmaster 2 Mk.44 (USA)
37 mm	M6 (USA)
75 mm	KwK37 (Germany) · KwK40 L48 (Germany) · M3 (USA) · M6 (USA) · StuK40 L48 (Germany)
76 mm	M1 (USA) · QF 17-pounder (Britain)
90 mm	M3 (USA)
105 mm	L7A3 (Germany) · M68 (USA)
155 mm	M126 (USA)
	Hungary
20 mm	Solothurn QF.36M
40 mm	37/42M · MÁVAG 41.M 40/51
75 mm	41.M · 43.M
105 mm	MÁVAG 40/43M
	Foreign:
30 mm	2A72 (USSR) · MK 30-2/ABM (Germany)
88 mm	KwK36 (Germany)
120 mm	Rh120 L/44 (Germany) · Rh120 L/55 A1 (Germany)
122 mm	2A31 (USSR)
125 mm	2A46 (USSR)

Israel tank cannons
30 mm	Bushmaster 2 Mk.44 (USA)
75 mm	SA50 L/57 (France)
84 mm	20pdr OQF Mk.I (UK)
90 mm	DEFA F1 (France) · M41 (USA)
100 mm	D-10T (USSR)
105 mm	M-51 (France) · M68 (USA) · Sharir
120 mm	IMI MG251
155 mm	M126 (USA) · M185 (USA) · Soltam M845