Woodie spine vs. carbon spine??

[Easykeeper]

Sorry for this long post but here goes.  I need some help matching the spine of an Arrow Dynamics Hammerhead to a wood shaft.  Just finished my first dozen wood arrows in many years, turned out pretty good but too weakly spined.

   

I started with Stu's calculator and a bunch of reading on here.  Then I got a dozen beautiful tapered Shurewood shafts from Rick at "The Feathered Shaft" and crested and finished them myself.  They were 84# - 87# spine, I'm shooting them out of a 64" Blacktail Elite, 54# @ 28" and I draw about 29".  I started with them full length, bare shaft tuning with 160gr. and 190gr. points, way too weak.  I ended up with them cut to 29.5" bottom of groove to base of point with 125gr. heads.  That's as short as I want to go and they are still way too weak.  Weak enough so that bare shafts plane almost two feet right at twenty yards.

 - This is what I want to know......What spine in wood, preferably Shurewood, do I need to match the spine of my  Arrow Dynamics Hammerhead arrows.  The Hammerheads shoot beautifully out of my bow.  The spine listed for the Hammerheads is 55# - 70#.  My HHs are cut to 30.5", 125gr. points.  I can shoot heavier points on the Hammerheads, but the 125grainers shoot perfect without fletching.  Heavier and I start to get planing to the right.  I'd like to get the point weight up in the 175gr. range.  According the the chart the HHs are spined more weakly that the woodies I made, but they shoot much stiffer.

How much more spine then these 84# -87# woodies do I need?  Thanks...  

[Shawn Leonard]

If they are in fact 84-87# spine than they are not too weak. For a woodie add 5#s spine for every inch over 28, so you would add 7#s roughly than 15# for the high performance bow that is 22# add that too the 57#s your bow is at your 29" draw and that is 79# spine spine woodie with 125 grain head, than ya can add 5#s for every 25 grains over 125 so you could shoot a 160 grain head off those shafts and be right on. I would check the spine for yourself, Sorry but woodies that truly spine over 85#s are rare. I was once told you may need to go thru 1000 shafts to find a few dozen that spine that high. I had a blacktail that drew 63#s at my 28.5 " draw and it shoot 85# spine wood perfect with 125 grain heads perfect. I would say a 77-80# spine with 125 grain heads cut to 29.5"s should be perfect for you. Shawn

[snag]

With drawing 29" you're actually pulling 57# so with 145-160gr tips you'd be good with 90#-95# spined Surewoods (no "h"). That's why you were showing weak.

[snag]

I don't know Shawn. I shoot 80-85's out of a 54#@28" Blacktail with beautiful arrow flight. Infact, that is the spine weight arrow that Norm gave me the day I picked the bow up at his shop. He handed me these arrows to try the bow out with. They flew so nicely I asked him what spine they were.

Surewoods can be found in the 100+ spine range by the way. I have some 90#-95# Surewoods.

[Easykeeper]

Thanks guys, it helps to have some experienced advice.  I still don't understand the spine numbers for the Hammerheads, they say 55# - 70#, nowhere near where I'm going to end up with Surewoods (Thanks snag   ).  I figured I'd call Rick next week and probably get Norms opinion too.  I'll probably try a dozen of really stiff shafts hoping I actually go a little over.  I can always leave them long and load up the point weight.  I don't want to make another dozen that is too weak.  Those 95# 'ers sound like the ticket.

This bow or my ragged release seem to like stiff arrows.  I was shooting Easton ACC 3-60s which are 340 spine, haven't a clue what that would equate to in wood.  Too bad there isn't a cross-reference chart showing how a 340 spine deflects compared to a 55# - 70# carbon compared to a ??# wood shaft.

[Shawn Leonard]

Sorry but something is wrong if you are shooting over 30# spine than what the bow is marked unless ya leave them long or heavy heads. Shawn

[snag]

I don't know anything about Hammerheads. So, I went on a website that sells them. They are listed as 90lb spine shafts with a .350 deflection. So I would think they could be tuned to your bow if cut down from the 30.5" you had them at. I shot CE Heritage carbons that were equal to 84# and had them loaded up with 225gr tips and they flew great. Carbons tune differently than wood in the way they react during archer's paradox.

[Easykeeper]

Shawn if there's is a weak spot in my system you need look no farther than the nut holding the bow.  I probably don't have a perfect release or form, but I can group the bare wood shafts.  Unfortunately the group is significantly to the right of fletched (except for the two that are out in the hayfield...     ).  I've considered that my release is causing contact, but can't find any marks on the bow or the arrows.  I have no way to check the spine myself, but am confident that Rick got it right.

snag - I started with the Hammerhead full length with 175gr. points.  They also planed right and bare shafts impacted right of fletched.  I ended up cutting them back to 30.5" with 125gr. points and bare shafts group right with fletched out to twenty five yards or so.  The Hammerheads end up very close to the 340 spine ACCs as far as length and point weight.  The Hammerheads are much heavier though, makes for a nice quiet bow...cheaper too.  

I'm going to try to build out the pad on the side of the window a little and see if that helps.  Someone else gave me that advice and it sounds like something good to try.  If nothing else, it's more information.

[Al Dean]

I'll probably be shot for this, but I think they take a 84-87 shaft then taper it.  The shaft is no longer 84-87 but probably 80-84 or so.  Of course this is just my opinion.