after polishing the nocks and trigger, i made a string for my jayhawk prod using 30 strands (15 loops)which comes to a 420 pound string on a 75 pound prod. i served it with the same thread. brace height was 3 1/4" and the power stroke is 9". on my second shot the string hit the bolt a little high flipping the forward end skyward resulting in a misfire and broken string. on the first shot the bolt hit something hard embedded in my styrofoam target snapping it in half. 5/16" x 16" port orford cedar with a 100 grain, 2 blade glue on point. bolt too light?
also wondering if bamboo would work ok for bolt shafts. the species of bamboo i have is small diameter, has long internodes and is extremely thick walled. it makes great arrow and atlatl dart shafts, so i'm wondering if it will work for bolts?
on my bows i usually make the string between 4 and 5 times the draw weight. though they are never dry fired and my arrows tend to be a bit heavy for the draw weight. the string i broke on my crossbow was 5.6 times the draw weight. how much heavier should i make them to make them a bit more forgiving of misfires?
i'm also wondering what my minimum assembled bolt weight should be for my crossbow?