155 mm SHELL HE M/77B
ROLE :
The 155 mm 77 B is a long range artillery ammunition designed to attack ground targets. The main characteristics are:-
a) Rapid and accurate firing at long ranges

b) Capable of firing various shells/propellant charges.

c) Superior mobility in both road and cross country. The 155 mm gun can be fired in the elevation of -3° to 70° and can be traversed 30° on either side. However the traverse of the gun is restricted beyond 50° elevation. Maximum muzzle velocity of gun is 0.827 km per second and the rate of fire is 3 rounds per 14 seconds.
FUNCTION :
When the gun is fired, the burning propellant charged rapidly generate gas pressure at the base of the shell and drives the shell through the barrel. The velocity varies depending upon the charge used.

Different types of fuzes can be used for the shell M/77 B viz. Zelar fuze. The Zelar fuze has 8 different setting modes. It is designed to meet the highest safety demands and has five different safety systems. If setting is for proximity circuit, the impact circuit is earthed.
PROXIMITY FUNCTION
i) Low sensitivity- Wet ground conditions
ii) High sensitivity Dry ground conditions
iii) Normal sensitivity Normal ground conditions
iv) Safe  
 
IMPACT FUNCTIONS
v) Long delay Recochet Burst
vi) Short delay Penetration Burst
viii) Instantaneous Action High sensitivity. For example - Snow covered ground.
viii) Instantaneous Action Normal sensitivity

The Zelar fuze has a back up function, if the normal function fails, the fuze function as a super quick impact fuze.

 
SPECIFICATION/CHARACTERISTICS :
a) Mass of the shell with fuze 42.6 kgs
b) Mass of shell without fuze 41.7 kgs
c) Length of shell with fuze 825 mm
d) Length of shell without fuze 728 mm
e) Filling type, standard TNT
f) Filling mass 8.0 kgs
g) Compatible fuzes Zelar, PDM 572C1
h) Primer used Primer M 191A-2
i) Compatible charges Green bag (Zone 3-5)
White bag (Zone 4-7)
Charge 8, Charge 9
j) Muzzle velocity of shell at charge 5 for green bag 368 m/s
at charge7 for white bag 578 m/s
at charge 8 690 m/s
at charge 9 821 m/s
k) Range 500 m to 24 km
l) Maximum permissible chamber pressure 440 Mpa
m) Shelf life 15 years
n) Operating temp. -20°C to +60° C.
o) Storage temp. Mean temp. less than + 32°C
Min. temp. -40°C
Max. Temp. +55°C +1140 W/M² Solar radiation, equivalent to approx. +70°C
 
QUALITY :
Quality is ensured at very stage of manufacture. Shells are filled and a carrying handle of ‘T’ shape if fitted under strict quality control and proof carried out for their performance requirements.
RELIABILITY :
Reliability of shells is ensured by independent testing of each sub systems/ sub assemblies and also further as a complete store for its functioning requirements.
PACKING :
The shells are packed in unit load in wooden pallet containing 12 shells in each unit.
STOWAGE DIMENSION OF UNIT LOAD :

Length

900 mm

Width

1060 mm

Height

570 mm
Mass of the unit load 556 kgs
 
HAZARD CLASSIFICATION :

Compatibility

D

Hazard Division

1.1

Fire fighting classification

1
Contact :
Marketing & Export Division
Ordnance Factory Board
Ayudh Bhawan
Government of India
Ministry of Defence
10A S. K. Bose Road. Kolkata - 700 001, India.

Tel: 0091-33-248 9027 / 248 2103 / 248 5077-80
Fax : 0091-33-248 1748/210 8235
Mail : ofbtrade@dataone.in
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