MIL-HDBK-785, MILITARY HANDBOOK: DESIGN OF TOWED ARTILLERY SYSTEMS (30 MAR 1990)., The purpose of this handbook is to present and illustrate design methods for towed artillery systems and their components. Towed systems are artillery weapons transported by prime movers that are separate from the artillery weapon. Towed artillery systems are capable of emplacement, delivery of fire, and displacement by a field artillery crew. The towed artillery weapon system consists of 1. Ammunition 2. Tube and breech 3. Recoil mechanism 4. Carriage structures 5. Mechanisms allowing for elevation, traverse, and emplacement 6. Fire control equipment.