Arrow Spine

[bigcountry]

Is this normal.  I am relatively new to the selfbow scene.  I have built one osage and building another.  I also one someone in Wa State built for me.  All of them, I need spines 12lbs or lower than the wieght.  I have to shoot 40-43lb spine POC with 125gr tip with my 54lb osage that is almost centershot.  And have to shoot the same 43-45lb spine out of another one I built that is pretty far from centershot and is 57lb bow.   I also tested out with 1816 alums and need 200gr head with a 30" arrow to shoot well out of my 54lb osage. 

They fly good, don't burn up as far as speed.  But I hit where I am aiming.  I just wonder if I have a bad release or these are typical numbers. 

[Justin Snyder]

It is actually fairly normal for a long bow to need spine 10# under bow weight. The center shot one should not be as bad.  This tells me that the bow you built is probably a little more efficient. The center shot bow probably has a lower string tension at brace.  Justin