Just for context, a stock Big Bertha (without a motor)—the whole model—weighs less than your proposed nose weight. The Estes BT-80 V2, which of course has larger-than-scale fins weighs about 6 1/2 ounces (well, mine does). This has a 24mm motor mount and doesn't go very far at all on a C11-3. It likes D12-5s or more.

So with a 10 ounce plus weight, you're looking at composite motors, I expect. You're basically looking at something not unlike a dual egg lofter, with lots of momentum at the end of the shock cord....

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Bernard Cawley
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