Rocketman is our current guru, but Gough Thomas had something to do with it...
Thomas and I were/are afflicted with two of the same maladies - mechanical engineering and an obsession with guns. Thomas published his work with a torsional pendulum in the 1960's. I never heard of him or his work until I started posting data in the late 1990's. In the resulting firestorm,someone pointed out, in my support, that Thomas had published this same sort of work. Thomas was disappointed that so few Brits were interested in the technology of guns and shooting. He did only a few guns to satisfy himself. So, I confess to following in his footsteps, but with a greatly expanded data base and broadened application.
MOI machines are calibrated with "bars" of calculated MOI.
DDA
