Wierd spine Q?

[Soonerlongbow]

My wife's self bow is 42# @ 26" (her actual length is 25.5) yet it shoots a vaned 27" Carbon Excel .340 with a 100gr tip like a dart to near exact POA-POI. Yet when she shoots my GT Tradionals 35-55's @ 30" spined .400 they fish tail and groups open up. Near exact opposite from her bow for me.

The Excels are my wheel bow shafts.

Her bow is around 1/4 off center.

I know to "go with what works" but just seems strange to me. Getting her some GT Nugent shafts and she ordered me a Griz Sticks with One Stringer wraps.

[BOHO]

where are the ones hitting that dont fly well? left or right?

[Soonerlongbow]

High left if I remember correctly, thats with the feathers on the Traditionals. I get the same flight but better groups with the vaned arrows.

[Rob W.]

Both are way stiff. Have you paper tuned?

Are you shooting vanes off the shelf?

[Soonerlongbow]

Off the shelf but does have mole skin. I know they are supposed to be way stiff, especially the .340's, yet fly near perfect, thats the really funny part.

[Soonerlongbow]

And havnt paper tuned either.

[mountain lion]

This might not make any sense but I had a kanati longbow that was 45# and showing that it needed a stiff arrow. Someone told me to move the nock point up so I moved it up and 1/8 inch and it corrected it. Don't really make sense to me but it worked.