South Africa's Denel armaments group is offering a new family of 155mm artillery shells optimized for the new longer 52-caliber barrels. These shells will also work in older 39, 45, and 47-caliber barrels. Caliber, in this context, reverse to barrel length. A 52-caliber weapon is 52x155mm long. The family includes both boat tail and base bleed shells. Base bleed shells have a slow-burning charge on the rear which creates a pocket of expanding gas behind the shell. This reduces air resistance and gives the shells about 5-10% more range. Users of Denel shells can switch from boat tail to base bleed in the field by obtaining the alternative rear module. The family of shells includes high explosive, improved conventional munition (which scatters bomblets able to penetrate the tops of armored vehicles and scatter fragments as well), screening smoke (chemically composed to block thermal viewers), illumination, red phosphorus, rocket-assisted, and practice shells. In trials, unassisted shells have reached 33,835m (30,951m when corrected to sea level) while assisted shells have reached 44,141m (40,230m at sea level).-- Stephen V Cole