I started a sinew bow a few weeks ago,, 48 inches,, I put about 1000 grains of sinew,, mix of horse sinew and elk,,
Got the bow strung and when I was tillering it out to about 18inches the sinew on one tip by the reflexed tip broke and came loose,,, I had to lay down,, whew
when I looked at the damage the wood was ok,, but I was very suspect about the horse sinew,, I could break a small strand of it easier than the elk back strap sinew,, so after much deliberation,, I carved the sinew off and started over, this time with all elk back strap,,, I didn't have much ,, I would say a couple of good layers maybe 400 grains,, I forgot to weigh it,,
got the new sinew on and let it dry about a week.. I know thats not enough,, but its so dry here and the sinew layer was thin,, I got the bow strung today and pulled it to about 20 inches it was about 50# and the tiller seemed pretty even, I did not put it on the tree,,
I got so excited that I decided to shoot it at the 20 inch draw and it shot nice,,, I got out the chrono
and shot a few arrows and it would shoot 153fps with a 475 grain arrow,, ok thats not screaming,, but for a 20 inch draw I thought that was pretty good,, so I shot it like that for the rest of the afternoon just having fun,, it was very accurate,, I would unstring and check the unstrung profile and it was nice,, still holding a little over 2 inches of reflex,, even with so little sinew on the back,,,, one elk back strap tendon,,
ok this is very exciting,, the bow had propeller twist and I thought i was going to have to heat it out,, but leaving it strung backwards while curing,, seemed to pull the tips in line quite a bit,, and after reading the thread on limb twist,, I took wood off the strong side and the tips lined up perfect,, finally I learned how to do that,,
one limb had reflex and the other deflex,, but when I shot it,, either limb on top shot great,,, I had in my mind I wanted to go to 24 inch draw, but the bow is so fun to shoot I am thinking of leaving it,,
it is a good example of how a sinew bow can shoot ok,, even if it is too long,, normal rule of thumb would be to have a bow about 40 inches for a 20 inch draw,, this bow shoots nice being 48 inches long,, or too long for accepted rule of thumb,,, I make my bows for deer hunting and 153fps with a 475 grain arrow is in my comfort range to shoot at deer,,
Now the side of me that wants to mess with everything and make it "better" is having a fit,, what if I draw it further ,, the performance will go up,,, maybe but if the bow starts to take set,(because of lack of sinew), it will off set the longer power stroke,, right?
I have enough bows to last a life time so I am going to try to put this aside and think about it before I change anything,,,
I included a full draw pic,,,, this is the first time I had seen the draw at 20 inches, I had the bow taper pretty even so was not to worried the way it was shooting,,,, ,not to bad,, I am sure I could make it look better if I increased the draw fine tuning the stiff spots,,,, but I don't think it will be any more fun to shoot,, thanks for listening,, B
