New LANL gas driven two-stage gun

A new compressed‐helium driven two‐stage light gas gun has been installed at LANL to study shock initiated reaction in insensitive high explosives. The gun (based on a design at Ernst Mach Institute) has a 100‐mm diameter by 7.6 long pump tube and a 50‐mm diameter by 7.6‐m long launch tube. The gas breech, capable of pressures up to 15,000 psi, has a volume of 42.5 liters and can be used in either a wrap‐around or double‐diaphragm mode. This breech was designed so we could use helium rather than powder combustion gases to drive the pump piston, eliminating the safety and cleanup problems assoicated with gun powder. Large hydraulic clamps (pressurized to 10,000 psi) are used to clamp the breech to the pump tube, the pump tube to the transition section, and the transition section to the launch tube. The target chamber was designed to allow the necessary room to do multiple magnetic gauging experiments. Gun control is accomplished using a MAC computer and LabVIEW control software.