An Automatic, Velocity Dependent Delay System for Use within and Beyond the Muzzle Blast Region of a Gun

Abstract : In ballistic research, it is quite often required to observe the projectile immediately after launch from the gun tube, while it is still in the muzzle blast region of the gun. Flash x-ray photography is an excellent method to record the projectile in this region for evaluation of the structural integrity and the projectile velocity. However, a precise time delay is necessary to assure that the x-ray unit is triggered at the proper time. Normally, the time delay is computed based on the expected velocity, and preset into the x-ray delay circuit. However, round-to-round variation in the actual velocity can result in the preset delay being inaccurate. This is especially true in research and development programs. A time delay system for use while the projectile is in the muzzle blast region has been developed which will automatically provide a trigger at the correct time regardless of the projectile velocity. Other application are possible, such as providing the proper time delay to transmit data in an automatic fuze setting system.