Israel's Soltam has released more details about its 155mm ATMOS-2000 artillery system. This is a truck-mounted self-propelled system, a new type of artillery that has appeared in larger quantities of late. While truck-mounted self-propelled systems lack the armor of tracked vehicles (and hence are as vulnerable to counter-battery fire as towed artillery), they are easier and faster to move. Most, including ATMOS-2000, have armored truck cabs to provide protection for the crew, but this is useless when the gun is firing. The ATMOS-2000 prototype uses a 52-caliber barrel for long range (41km with base-bleed ammo, 30km with the new NATO L15 shells, 24km with older M107 shells), but can also mount shorter-barrels such as 45-caliber and 39-caliber. (A 52-caliber weapon is 52 times as long as the 155mm bore.) The prototype is built on a Tatra 6x6 heavy truck chassis that was built in India, but the weapon can be built on any similar truck chassis. Two large spades are deployed from the back of the truck to stabilize it as a firing platform. The four-man crew can sustain four rounds per minute, with a burst rate of 9 rounds per minute. A flick-rammer is provided to reduce crew fatigue. While Soltam built the prototype as a private export venture, it has a target market. Soltam has won a contract to upgrade 180 Russian-built 130mm towed M46 field guns in the armory of the Indian Army to NATO-standard 155mm barrels (of either 39-caliber or 45-caliber). It happens that the ATMOS-2000 can be built with the saddle and elevating mass of the M46, and India is known to be in the market for mobile artillery. While India has only tested tracked systems, Soltam is trying to convince the Indians that truck-mounted artillery would be cheaper to buy and operate, and nearly as effective.--Stephen V Cole