175 mm Projectile, HE, M437A1/M437A2

it remains in service with several other nations throughout the world and the 175 mm HE M437A1 and/or M437A2 projectiles remain available for production in several countries. Known users of the 175 mm M107 Self-propelled Gun include the following: Greece (12); Iran (30, some destroyed); Israel (140); South Korea (no definite information regarding numbers available but may be about 100); and Turkey (36). Many of these guns are being, at best, placed in reserve as they are replaced by MLRS rocket systems. Description The 175 mm HE M437A1 and M437A2 are classified as separate loading ammunition. The only difference between the 175 mm HE M437A1 and M437A2 is that the M437A1 is filled with 13.608 kg of TNT, while the M437A2 is filled with 14.1 kg of Composition B plus a supplementary pressed TNT charge in an aluminium container; the supplementary charge, which weighs approximately 136 g, is removed when a long intrusion proximity fuze is fitted. The projectile body is forged steel with a streamlined ogive, a distinct 'waist' profile noticeable just behind the bourrelet, and an 8º boat tail. The baseplate is welded into position. A 625 mm wide gilding metal drive band encircles the projectile and a nylon obturator band, 145 mm wide, is located behind the rotating band. The obturator band, which seals propellant gases behind the projectile, is discarded after the projectile leaves the gun muzzle. The 175 mm HE M437A1 and M437A2 are fired using the M86A1 propelling charge assembly. This is made up of three increments of bagged M6 multiperforated propellant weighing a nominal 24.95 kg. The propellant is contained in sealed white acrylic-viscose rayon cartridge cloth bags, with the three increment bags taped together. Technical references retained in this configuration include MKE-MOD, 257 mm, 203 mm, 190.5 mm, 26.3 kg, 7.94 kg, 406 mm, 838 mm, 67.45 kg.