Here are the promised chrono results......
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To recap the bow is 51 lbs @ 26 and the arrow I was shooting is 450 grains so I make that 8.8 grains per pound
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Sorry for the dodgy screen readout....a mis fired .22 caused that!
209.6
208.0
212.0
212.0
I think that's pretty darn speedy!
I will have to make up a 510 grain arrow and see what this bow does at 10 g.p.p.
Anybody good at maths to work it out?