MRBPS is being investigated as a replacement for black powder in the form of delay and propelling charges for the M74A1 Air Burst Simulator. MRBPS is produced via evaporative mixing of the composition as a paste in ethanol. Increasing mix speed near the end of the mix cycle enhances the bulk density and uniformity of prills produced thereby. Milling these prills without additional densification produces ordnance grade granules that yield comparable maximum pressures to those produced by BP. This was substantiated through side-by-side comparisons of the two granular propelling charges in M74A1 impulse cartridges attached to a 50-cc closed bomb. Slightly coarser granules of MRBPS are predicted to produce comparable rise times to those of Class 5 BP used in the impulse cartridges. The burn time of MRBPS pressed into M74A1 fuse columns with the same delay charge height is about 40% longer than that of BP. Pressed columns of MRBPS are less friable than BP. The burn time of MRBPS delay fuses is insensitive to pressing pressure and is a linear function of charge weight.
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