at first blush.....about 71%
but, after I posted that, it occurs to me that there are other factors in play with changes in barrel lenght. shorter barrel means less friction or drag on the pellet...
And the whole pneumatic propulsion thing can, at time (har, most of the time) be counterintuitive, which is part of why I'm hedging/waffling on the 71%.
your 2240 example indicates a shortening of 50% only reduces MV by 20%. Definelty nonlinear and counterintutive.
Flashing back to some research you did as the ramp up to the AC efforts, are we back to most of the energy given to a pellet being developed _very_ early on in its travel trhu the barrel.
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