Mach one impact test apparatus utilizing an 18.4-mm-bore gas gun with a novel decelerating device.

The design and operation of a helium-gas-driven gun capable of operation to Mach one is described in this report. The gun utilizes a unique tapered-tube decelerator that captures the sabot and prevents gas discharge from the muzzle. This feature makes it possible to operate the gun in a normal laboratory environment without excessive safety precautions.