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Chapter 3. BallistaMail > Skein Plates, Supports, and Their Attendant Mysteries - Pg. 70

Ballista Mail Spinnin' Metal Tubes o' DeathTM When I first started making these things, I put a stupid amount of effort into determining the (theoretical) most effective projectile (officially called a dart). Stability in flight was the main problem to overcome. There's not really enough room for full-scale fletching on a pint-sized ballista (at least not on the ones I build), so I resorted to trying to tune the center of gravity on the darts so that they could take a huge push from the rear without wobbling out of control once they left the guide rails. To that end, I put together some test projectiles out of 3 / 8 " brass tubing with 1" wooden balls as the "arrowheads," the plan being that I'd be able to press-fit balancing weights up the patterns around a nonspinning sphere that make a knuckler jump around, seemingly at random, as it heads to the plate are the factors in play here, and without some kinda rotational gyroscopic thing going on, you're more or less going to have to live with a bit of wobble. Ballistics is an unforgiving science. Putting a rifling twist on 1 / 4 "-high fletching down the whole length of the shaft is about the best solution I could come up with, but even then, it's a compromise. Pain in the ass to fabricate, too. Unsafe high-performance ballista bolts are an entirely different story. Just by losing the end caps and using a Dremel to shape an aerofoiled set of rotation-inducing blades on the front end of the