US Cartridge, 4.2 inch Chemical, T172 Modified
This projectile was designed for use in either the M2 or the M30 4.2-inch mortar. The projectile accommodated standard point detonating or variable time fuzes. The ratio of filling to explosive was approximately two to one. The T172 (modified) was designed to replace the T172 completed in 1951, which was ballistically unstable. The latter projectile was modified to make it stable at ranges from 600 to 4,000 yards for the M2 mortar and from 600 to 6,000 yards for the M30 mortar.
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