Spine calcs - Parallel vs Taperded shafts

[Rocky Weeks]

Been considering getting some new arrows and looking at the tapered wood shafts.

    I understand how spine calculations work on Parallel wooden shafts but ciphering in the effect of Taper on a shaft has me confused.

    I've talked to some arrow makers have gotten suggestions but I'm still confused. They seem to be telling me that I can jump up 5 or 10#s in spine with a tapered shaft as compared to a parallel shaft.

    Is there an unwritten rule when comparing parallel shafts to tapered shafts.

    I.E. 40-45# Parallel shaft = xx-xx# Tapered shaft

    If you gain an average of 5#s for every inch trimmed from a parallel shaft does the same hold true for tapered shafts?

    Any opinion or verifiable information is much appreciated.

[Rocky Weeks]

TTT

[Stone Knife]

I just shoot the same spine on tapered as I do with parallel.

[Bill Carlsen]

I used to make custom arrows and tapered and barrel tapered them on request. Normally I found that if I took a parallel shaft of a particular spine and did a single taper on the nock end I might loose 1# in spine. When the same shaft was barrel tapered it lost almost 5# and in some cases 10# from the original spine of the parallel shaft. Once the shafts are tapered they should still be in the same spine range that you normally shoot. In other words, if you shoot a normal spine of 55# a barrel tapered shaft should still be spined 55# but it probably started out as a 60-65 parallel shaft.

[laddy]

I had a set of barrel tapered arrows, there was magic in them that I never could understand.  I have not seen any that I could afford since.  Why does that barrel taper make so much difference for me? Is it because that they stated out ten pounds heavy?