60mm Mortar Ammunition And Fuzes
Gary's U.S. Infantry Weapons Reference Guide

DESCRIPTION

Mortar ammunition is considered semi-fixed because the propelling charge is adjustable. On 60mm rounds, bags of granular or horseshoe-shaped propellant are attached to the fins or boom.

All 60mm mortar rounds, except training rounds, have three major components - a fuze, body, and tail fin with propulsion system assembly.

AMMUNITION

Ammunition types: FM 23-90:  M720, M888, and 60mm B ammo
60mm mortar ammunition.
Model Type Length Weight Minimum - Maximum Range Fuze
M3 Sabot Training Device TP 15.618 in (397 mm) 6.25 lb (2.83 kg) ? ?
M49A2, M49A3 HE 9.61 in (244 mm) 3.05 lb (1.38 kg) ? - 1,969 yd (? - 1,800 m) M525
M49A4 HE 11.61 in (295 mm) 3.15 lb (1.43 kg) 49 - 2,001 yd (45 - 1,830 m) ?
M50A3 TP 11.61 in (295 mm) 3.15 lb (1.43 kg) ? ?
M69 Training 7.72 in (196 mm) 4.43 lb (2.01 kg) ? ?
M83A3 ILLUM 14.28 in (363 mm) 4.15 lb (1.88 kg) 793 - 1,039 yd (725 - 950 m)
Diameter of illumination: 984 ft (300 m)
?
M302A1 WP ? ? 38 - 2,001 yd (35 - 1,830 m) ?
M302A2 WP 13.07 in (332 mm) 4.10 lb (1.86 kg) ? ?
M720 HE 14.85 in (377 mm) 3.75 lb (1.7 kg) 77 - 3,828 yd (70 - 3,500 m) MO M734
M720A1 HE 14.84 in (377 mm) 3.65 lb (1.66 kg) ? MO M734A1
M721 ILLUM 16.58 in (421 mm) 3.76 lb (1.71 kg) 219 - 3,828 yd (200 - 3,500 m)
Diameter of illumination: 1,640 ft (500 m)
MTSQ M776
M722 WP 14.84 in (377 mm) 3.7 lb (1.68 kg) 77 - 3,828 yd (70 - 3,500 m) PD M745
M722A1 WP 14.84 in (377 mm) 3.79 lb (1.72 kg) ? ?
M766 SRTR
Short-Range Training Round
TP 11 in (279 mm) 2.9 lb (1.32 kg) 61 - 588 yd (56 - 538 m) Practice M779
M767 ILLUM, IR 16.80 in (427 mm) 3.76 lb (1.71 kg) 219 - 3,828 yd (200 - 3,500 m)
Diameter of illumination: 1,640 ft (500 m)
MTSQ M776
M768 HE 14.84 in (377 mm) 3.65 lb (1.66 kg) ? PD M783
M769
Full Range Practice Round
TP 14.88 in (378 mm) 3.75 lb (1.7 kg) ? Practice M775
M888 HE 14.74 in (374 mm) 3.75 lb (1.7 kg) 77 - 3,828 yd (70 - 3,500 m) PD M935

M49A2 HE

FM 23-90: M49A2
The M49A2 HE round is painted olive drab. It consists of a hollow body, fin assembly that screws on the rear of the body, and M525 fuze that is attached to the front of the round. A TNT bursting charge is contained in the body and is ignited by the booster charge in the fuze upon impact. The fin assembly contains the ignition cartridge and provides a means for attaching the propelling increments. The fins keep the projectiles stable in flight.

Each round comes in a separate fiber container complete for firing.
M50A2 TP

This round is designed to give mortar crews practice in firing and technique of fire without the expense incident to firing HE ammunition. On impact, the practice round emits a puff of white smoke that is clearly visible to the observer. This round differs from the HE round described above in color and filler only. It is painted blue.
M720 HE

The M720 60mm High Explosive (HE) cartridge with M734 Multi-Option Fuze is designed for use with the M224 Lightweight Company Mortar System (LWCMS) in all light infantry battalions including Airborne, Air Assault and Ranger. The round is used against personnel and materiel providing both fragmentation and blast effect. It consists of a multi-option fuze, tail assembly, and projectile body with a TNT or composition B explosive fill.

This is a training standard item used in both training and combat.

Type Classification Date: JAN 1986. Unit cost: $497 (Fiscal Year 2005).
M720A1 HE

The M720A1 60mm HE cartridge with M734A1 Multi-Option Fuze incorporates several new design features, which significantly decreases its sensitivity to unplanned stimuli (enhanced insensitive performance). A new insensitive main charge called PAX-21 has replaced the composition B explosive. Additional changes have been made to the fuze adaptor, packaging and fuze explosive charge. Lethality is maintained by using a high fragmentation steel (HF-1) shell body. The M720A1 also incorporates the highly reliable and countermeasure resistant M734A1 Multi-option fuze.

This is a training standard item used in both training and combat.

Type Classification Date: NOV 2001. Material Release: SEP 2004. Unit cost: $489 (Fiscal Year 2005).
M721 ILLUM

The M721 60mm mortar illuminating cartridge is designed for use with the M224 lightweight company mortar system (LWCMS) in all light infantry battalions including Airborne, Air Assault and Ranger. The M721 will provide visible light illuminating capability at the same effective range as the companion High Explosive (HE) Cartridges, M720/M720A1 (Range 3,200-3,800 Meters Maximum).

The M721 is ballistically similar to the M720A1 HE Cartridge, allowing a gun to illuminate and fire on the same target without adjustments. The M721, and infrared illuminant, M767 rounds are identical except for the composition of the illuminant.

This is a training standard item used in both training and combat.

Type Classification Date: SEP 1984. Unit cost: $604 (Fiscal Year 2004/2005).
M722 WP

The M722 60mm WP smoke cartridge is used on the M224 Lightweight Company Mortar System (LWCMS). It provides a smoke cloud for spotting or marking a target area. The M722 is assembled with the M745 point detonating fuze which functions on impact. The cartridge has in integral burster charge, white phosphorous filler, a thin wall shell, fin assembly, a four increment M204 propelling charge, and an ignition cartridge.

Type Classification Date: SEP 1991. Unit cost: $329 (Fiscal Year 2002).
M766 SRTR

FM 23-90: M766
The M766 60mm mortar cartridge is a low-cost, short range, refurbishable practice round that will replace a majority of the standard High Explosive (HE) rounds used in the 60mm mortar training strategy. It consists of a M779 point detonating practice fuze which provides flash, bang and smoke; a steel body which approximates the shape of the 60mm HE service round; and an ignition cartridge which provides the limited propulsion requirement.

After firing, the round is retrieved and refurbished. Refurbishment will be accomplished by replacing the fuze, the obturating ring, range adjustment plugs, the ignition cartridge, dud plugs and the breech plug. The round is designed to be used at least 25 times (I.e., original firing plus 24 refurbishments).

The M766 short-range training round (SRTR) cartridge can be fired from the 60mm mortar using standard sight and fire control equipment. A 60mm subcaliber device can be inserted in the 4.2-inch mortar to fire the M766 for training 4.2-inch heavy mortar platoons.

The cartridge is blue with white markings and one brown band.

The M766 uses an M779 PD fuze, which produces a visible flash, a cloud of smoke, and an audible sound on impact for spotting purposes. The M779 has multioption type (PRX/NSB/IMP/DLY) dummy settings to simulate an M734 multioption fuze.

This is a training-unique item; not used in combat.

Type Classification Date: JUN 1993. Unit cost: $82 (Fiscal Year 1999).

M767 IR ILLUM

The M767 60mm mortar infrared illuminating cartridge is designed for use with the M224 lightweight company mortar system (LWCMS) in all light infantry battalions including Airborne, Air Assault and Ranger. The M767 provides infrared illumination which greatly enhances the effectiveness of night vision devices at the same effective range as the companion High Explosive (HE) Cartridges, M720/M720A1 (Range 3,200-3,800 Meters Maximum).

The M726 is ballistically similar to the M720A1 HE Cartridge, allowing a gun to illuminate and fire on the same target without adjustments. The M726, and visible light illuminant, M761 rounds are identical except for the composition of the illuminant.

This is a training standard item used in both training and combat.

Type Classification Date: SEP 1999. Unit cost: $604 (Fiscal Year 2004/2005).
M768 HE

The 60MM Mortar High Explosive/Point Detonating (HE/PD) cartridges are designed for use with the M224 Lightweight Company Mortar System (LWCMS) in all light infantry battalions including Airborne, Air Assault and Ranger. It will use the new M783 dual safety, point detonating/delay fuze. It will also use PAX-21 insensitive explosive fill, and a new fuze adapter and packaging that will enable the round to meet most insensitive munitions requirements. Lethality is maintained by using a high-fragmentation, steel (HF-1) shell body. The tail assembly and propulsion system will be common to all other 60mm rounds.

This round will be used primarily in training because it is significantly less expensive than the M720A1, the preferred war-fighting round. However, the M768 will be highly lethal and can be used in combat.

This is a training standard item used in both training and war reserve.

Type Classification Date: NOV 2001. Material Release SEP 2004. Unit cost: $353 (Fiscal Year 2005).
M769 Full Range Practice Round

The M769 cartridge is designed for use with the M224 Lightweight Company Mortar System (LWCMS) in all light infantry battalions including Airborne, Air Assault and Ranger. The M769 is a low-cost, full range, practice round that will replace a percentage of the standard High Explosive (HE) rounds used in 60mm mortar training.

The round consists of a M775 point detonating practice fuze which simulates the multi-option fuze and provides flash, bang and smoke; a steel body that approximates the shape of the 60mm HE service round; and a fin assembly, ignition cartridge and propelling charge that make up the propulsion system.

This is a training unique item; not used in combat.

Type Classification Date: SEP 2001. Material Release: MAR 2004. Unit cost: $138 (Fiscal Year 2005).
M888 HE

The round is used against personnel and materiel providing both fragmentation and blast effect. It uses the M935 point detonating fuze, fin assembly, and a projectile body with a TNT explosive fill.

Type Classification Date: 1986. Unit cost: $67 (Fiscal Year 2002).

FUZES

FM 23-90:  M734
M734 Multioption Fuze

This fuze for the M720 and HE round can be set to function as proximity burst, near-surface burst, impact burst, or delay burst.


Tools are not needed to set this fuze. The setting can be changed any number of times before firing without damaging the fuze. The fuze has no safety pins or wires to reduce preparation time.

M734A1 Multioption Fuze

This fuze is for the M720A1 HE round. When the fuze is set in the proximity mode, it functions at a height over the target that is optimized for lethality.

The M734A1 fuze is common to the 60mm HE, 120mm HE and 120mm WP Smoke rounds.

Unit cost: $230 (Fiscal Year 2005).
M775 PD Practice Fuze

TM 9-1315-252-12&P: M775 Fuze
Point detonating practice fuze. Produces a visible flash, a cloud of smoke, and an audible sound on impact for spotting purposes.

Has multi-option type (PRX/NSB/IMP/DLY) dummy settings to simulate an M734 multioption fuze. The M775 PD fuze functions on impact with superquick action only. Setting of fuze is for practice only and has no effect upon actual functioning.

This is a training unique item; not used in combat.

Unit cost: $16 (Fiscal Year 2005).

M776 MTSQ Fuze

Is a mechanical time superquick (MTSQ) fuze.

Unit cost: $140 (Fiscal Year 2004/2005).
M783 PD Fuze

Dual safety. Point detonating/delay fuze.

Unit cost: $140 (Fiscal Year 2005).
M935 PD Fuze

This point detonating fuze for the M888 HE round can be set to function as superquick (SQ) or delay (D). FM 23-90:  M935