In 2008 Canada started a Technology Demonstration Project (TDP), entitled Revolutionary Insensitive, Green and Healthier Training Technology with Reduced Adverse Contamination (RIGHTTRAC). This five-year project aims at demonstrating that, at comparable performance, green and Insensitive Munitions (IM) are a viable option that can ease the environmental pressure on range and training areas (RTAs) and minimize the health and safety hazards for the users. It is known that hot fragments generated during the impact of a bullet, a shell casing fragment or a shaped charge jet (SCJ) may penetrate the cartridge casing and induce propellant ignition. A laboratory scale Hot Fragment Conductive Ignition (HFCI) test was set up to determine the relative ignitability of grain propellants in response to hot fragments of different weights, previously heated to various temperatures. The test was validated on six different gun propellant formulations, which were previously evaluated via bullet impact and shape charge field tests. Very good correlations were obtained between the HFCI tests and the bullet impact field tests, confirming that when properly employed, the HFCI can be a quicker and cheaper complement to the classical IM field tests. Good mechanical properties are very important for propellant grains, as any premature fracture of the grain can create an unexpected change in the pressure rise inside the gun and, consequently, can seriously affect the safety of its operation. A Drop Weigh Test (DWT) was used to measure the mechanical properties of gun propellant grains by measuring the stress-to-strain variation at fairly high strain rates. The measurements were conducted at three different temperatures (-54°C, +21°C and +60°C) for six gun propellant formulations and validated using mid-combustion interrupted burning tests in a 30-mm gun. The results from DWT, showing a close correlation with the interrupted burning tests results, demonstrated that two of the tested formulations had unsuitable mechanical properties at -54°C and +60°C, consequently making the gun operation unsafe under these extreme environments.
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