M85 (12.7 mm)

The M85 on top of the XM-1 (GM)

Description

The M85 is an American .50 cal (12.7 mm) heavy machine gun. The machine gun is mainly found in place of the Browning M2HB (12.7 mm) machine gun, on some high rank American tanks (mainly as a commander's gun on the M48 and M60 Patton series). Being a 12.7 mm heavy machine gun the M85 has a reasonable amount of armour penetration, and higher damage output than medium and general purpose machine guns. This makes it much more effective at engaging weakly armoured enemy tanks, as well as aircraft.

Vehicles equipped with this weapon

• M60
• M60A1 "D.C.Ariete"
• M60A1 (AOS)
• M60A1 RISE (P)
• M60A2
• M60A3 TTS
• ␗M60A3 TTS
• XM1 (Chrysler)
• XM1 (GM)
• XM803

General info

The M85 is a fairly standard 12.7 mm heavy machine gun. Despite being a completely separate weapon, it preforms almost completely identically to the much more widespread Browning M2HB (12.7 mm) heavy machine gun.

Available ammunition

The M85 can only be equipped with one ammo belt consisting of four M8 Armour-piercing incendiary (AP-I) bullets, followed by a single M20 Armour-piercing incendiary tracer bullet.

Penetration statistics
Ammunition	Penetration @ 0° Angle of Attack (mm)
	10 m	100 m	500 m	1,000 m	1,500 m	2,000 m
AP-I	23	22	16	10	6	5
API-T	23	22	16	10	6	5

Shell details
Ammunition	Velocity (m/s)	Projectile Mass (kg)	Fuse delay (m)	Fuse sensitivity (mm)	Explosive Mass (TNT equivalent) (g)	Normalisation at 30° from horizontal	Ricochet
							0%	50%	100%
AP-I	887	0.0403	N/A	N/A	N/A	+2.0°	47°	60°	65°
API-T	887	0.0403	N/A	N/A	N/A	+2.0°	47°	60°	65°

Comparison with analogues

The M85 performs functionally identically to the Browning M2HB (12.7 mm) machine gun found on most previous American tanks, as well as in other nation's tech tree. Like the M2HB it has a slightly lower rate of fire than other 12.7 mm machine guns, but has a larger belt capacity.

Usage in battles

Unlike lower calibre machine guns the M85 has enough penetration to be able to penetrate the armour of lightly armoured tanks (or the side / rear armour of some more heavily armoured tanks, bullets can also sometimes make it through armour holes such as the turret ring, or mg port of tanks, injuring crew members. Like all other machine guns it can be used for incapacitating exposed crew members, as well as marking enemy vehicles and obscuring the view of enemy players (shooting at their gun sight). It also does more damage to enemy aircraft than lower calibre machine guns, and is usually mounted on top of the turret, making aiming at aircraft much easier than with a co-axial gun. Clearing trees and bushes is another use.

Pros and cons

Pros:

• Enough penetration to damage some enemy vehicles
• Good belt capacity
• Rate of fire is ok

Cons:

• Slower rate of fire than Soviet 12.7 mm machine guns

History

The M85 is an American .50 cal heavy machine gun, which like the Browning M2HB chambered the .50 BMG (12.7×99mm NATO) round. In 1951 the US army started a program to produce a new .50 cal machine gun for ground and tank applications, replacing the extensively used Browning M2HB machine gun in those roles. The new weapon would have to be lighter and more compact than the M2HB, have a better rate of fire, and require reduced maintenance. In early 1956 the General Electric T175 prototype was selected for further development (with work on other weapons stopped) and in 1959 the T175E2 was adopted for production as the M85.

The weapon was substantially smaller and lighter than the M2HB, and had a fixed head-space (removing the need for head-space adjustment, which was regularly required on the M2HB). Although the rate of fire was not substantially improved compared the M2HB, the M85 was able to switch below low and high fire rates, unlike the M2. The weapon was fitted predominantly on the M48 / M60 "Patton" series of tanks, as well as the LVTP-7 amphibious vehicle. Despite it's theoretical improvements over the M2 the M85 shared a similar fate to the M73 (7.62 mm) machine gun. In service the weapon proved to be extremely complex compared to the M2 and rapidly became unpopular with tank crews due to very poor reliability. Due to its poor reliability the M85 was not fitted to the new M1 Abrams, and was eventually phased (as the M48 and M60 tanks left service). Ironically The M85 was replaced in service (on the LVTP-7 and M1 Abrams) by the Browning M2HB, the very weapon the M85 set out to replace.

A version of the M85 was designed to replace the M2 in infantry use, and designated M85C. Like the original M85 it proved to be extremely unreliable and unpopular during testing and was never adopted.

Media

Images

• 

  The M85 on the XM-1 (GM)

See also

• Browning M2HB (12.7 mm)

External links

• [Wikipedia] M85 machine gun
• Modern Firearms - M85

Tank machine guns
USA
7.62 mm	M37 · M60D · M73 · M240 · M1919A4 · Mk.52
12.7 mm	FN M3P · M2HB · M80 · M85
Germany
5.56 mm	MG4
7.62 mm	C6 · MG3A1
7.92 mm	MG13 Dreyse · MG34 · MG37(t) · MG42
12.7 mm	S.MG.50
USSR
7.62 mm	DT · PKMB · PKT · PKTM · RP-46 · SGMT
12.7 mm	DK · DShK · 6P49 · NSVT
14.5 mm	KPVT
Britain
7.62 mm	Browning MG4 · L3A1 · L8A1 · L8A2 · L37A1 · L37A2 · L94A1
7.7 mm	Vickers
7.92 mm	BESA
12.7 mm	L21A1
Japan
6.5 mm	Type 91
7.62 mm	Type 74
7.7 mm	Type 97
12.7 mm	Type 60 (B)
China
5.8 mm	QJT
7.62 mm	Type 55 · Type 59 · Type 86
12.7 mm	QJC88A · Type 54
14.5 mm	QJG02
Italy
7.62 mm	Beretta MG42/59 · FN MAG 60-40
8 mm	34/40M · Breda Mod. 38
13.2 mm	Breda Model 31
France
7.5 mm	AAT-52 · MAC 31
7.62 mm	A-A-F1N
8 mm	Hotchkiss Mle 1914
Sweden
6.5 mm	ksp m/14-29
7.62 mm	ksp 39 C · ksp 58 · ksp 94
8 mm	ksp m/36 · ksp m/39B
12.7 mm	ksp 88