One of the most frequently asked questions is “How much lift powder do I need for my shell?”. Unfortunately, the answer is not an easy one. The first reason is a lack of consensus regarding the optimum height to which various sized shells should be propelled. Of course, it is a requirement that burning components must not fall to the ground, but that is where the consensus ends. For a 3-inch shell, is 250 feet high enough or is 450 feet required? The second reason is that after deciding on the proper height, there are still a large number of other variables that determine the needed weight of lift powder. Among the variables are:
• Shell Type (cylindrical or spherical),
• Shell Weight,
• Shell Size (diameter),
• Shell Length (for canister shells),
• Lift Powder Grain Size,
• Lift Powder Quality (if it is not a commercial grade),
• Mortar Length,
• Loading Space (volume between bottom of mortar and shell), and
• Shell Clearance in Mortar.
Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 1, (1981-1989), pp 124-127
(K1_124)
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