Chronographed the bow today with a 400 grain arrow and a 320 grain arrow, 10 gpp and 8 gpp.
I'm pretty chuffed with the results, actually!
With a 26" draw on a 21" power stroke I got consistent readings at 10 gpp of 168-169 fps, with just a rather stretchy polypropylene string. At 8 gpp I got highs of 185 fps.
The fact that the wood is so light probably helps a lot.
After shooting it has just 1.5 cm of string follow. Still, my next sisal backing will be with denser wood. Got some plum, norway maple and hawthorn waiting.
but first some finishing to do, so for once I can show something close to a finished bow
Joachim