My ancient old target did not keep the bare shafts pointing the same repeatably. So, I decided to try a paper tune. Got it set up using rifle target paper, which is kind of stiff. 6ft from tip to tartget.
The Origianl Centershot 500 carbons were far to weak. Even at their shortest (28") and only 150 grains pile weight they showed weak spine with a 1 1/2" gash in the paper.
So I referenced 3Rivers' spine calculater and picked up some Easton Blood Line 400s. Paper tuned with two different front end pile weights (150 gr and 175 gr) on two bare shafts. Worked my way from 31" long in 1/2", then 1/4", and then finally 1/8" cuts down to: 29 3/4" for the 150 gr and 29 1/8" for the 175 gr. Started out with a 3" gash on one of them to just almost bullet holes.
The Bloodline's are very light shafts gr/inch at 7.7 gr/in. So, I get 18% FOC for the 150 gr and 20% FOC for the 175 gr set up. Need to fletch them and see how they fly!
FYI: My wife thinks I've lost it with switching arrows and all thig paper tuning. She may be right. It's hard to tell sometimes.
Last edited by Gun_Geezer; 07/07/20.
