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RobD
10-10-2010, 05:55 PM
I have been shooting all off season with my Left Handed 2009 Firehawk, 29 DL , 67 DW Ripcord drop away rest. I am using Gold Tip expedition 5575 with a 400 Spine - 100 grain tips. I Have it sighted in to 80 yards. Very tight groups.Better then my Mathews DTX, so I decided To use it for Hunting this year.
I have been Broadhead tuning it today. Using Muzzy fixed blades,I weighed them and they weight the same as my FP.The closest I can get my broadheads are 2" to the right of my Field Points.It is perfect up and down. Since I could not get them hit the same spot. Being that somethings wrong, I started retuning the bow from scratch. I did a walk back tuning, which needed no adjustment. Then I tried to paper tune it. The best I could get it was Tip was hitting 1/2 inch right of tail. Which that being said, my rest is right back were I started. The only thing I can think of is spine is off. I check the gold tip spine chart and it says that my arrow spine should be 400 at 29" arrow. My arrows are 28 3/4.
I was browsing thought the other archery forum. Found a thread from a couple year ago saying that if your BH are longer then your FP you should go with a little stiffer spine.I am thinking of changing to GT 7595 which is 340 spine. What happens if the arrow spine is to stiff. Any Information would be great.

J758
10-10-2010, 06:22 PM
If I were u I'd paper tune my BH. Then go from there. Seems like to me under spine would give u issues. Stiffer arrow less flex. You shoot fingers? More side to side action there goin on than a release.

RobD
10-10-2010, 06:38 PM
I shoot with a release. Sorry forgot to mention that. Never heard of paper tuning with a BH on.

J758
10-10-2010, 07:10 PM
Sorry. Didn't mean paper tune BH. Have paper tuned again. Then go from there. Also check for wobble roll em on a flat surface and see if maybe your insert isn't sitting right. I had this problem with my muzzy 125 and xx75 arrows. Had one insert just cramed in there with a bunch of glue. (From dicks)

J758
10-10-2010, 07:18 PM
Sorry. Didn't mean paper tune BH. Have paper tuned again. Then go from there. Also check for wobble roll em on a flat surface and see if maybe your insert isn't sitting right. I had this problem with my muzzy 125 and xx75 arrows. Had one insert just cramed in there with a bunch of glue. (From dicks) fixed blades must sit true on your insert or square from my experience. Rolled my arrows on the edge of the table and all wobbles. I made dicks re do em

RobD
10-10-2010, 07:38 PM
I tried changing arrow shafts, Thinking the same thing maybe insert or arrow bent. Didn't make a difference. If a heaver spine arrow won't hurt anything then I think I will do that. I have never had this problem before. I have had many bows in my time. Had this one BH tuned last year with these arrows and BH, but It was only at 63# DW. Thats another reason why i'm thinking its spine issue.

bfisher
10-10-2010, 08:31 PM
Don't rely on Gold Tip's charts. They aren't accurate. Use Easton's charts for checking spine selection. In short the 5575 is underspined for your setup. Easiest and cheapest way to verify this is to take two turns off the limbs and check again. If it works then you have your answer. Then you have a choice to make. Shoot at the reduced draw weight (my recommendation) or get stiffer arrows (340 spine is my recommendation) which to my way of thinking is a complete waste of monetary resources at this point.

For wat it's worth the length of a broadhead does not change the spine of an arrow compared with field point. It does shange the FOC somewhat, but very minimal.

RobD
10-10-2010, 08:37 PM
Thank you very much. That answers my Question to a T. I will back it down so I don't waste my 2 dozen arrows. Guess I will go back to somewhere in the 60-63 LBS area till I need new arrows. Then bring it change to a larger spine once I ruin these.One more Question if I change to the 7595 does that arrow weight more then the 5575. Does a stronger spine arrow weight different? Thanks again for the very detailed info. :D

bfisher
10-11-2010, 04:15 AM
Comparing black shafts against black shafts in the XT version the 7595 is .7 gr/in heavier than the 5575. It would be the same for Expeditions. That would mean an added 20 grains or so for a 28" arrow. Speed difference would be a maximum of 10 fps, hardly noticable at any average hunting distance. If you want to spend more money you could always choose the Velocity 300 with virtually no speed change. The arrow would be on the stiff side, but would still probably work OK with broadheads.

Destroyer
10-11-2010, 04:31 AM
I will back it down so I don't waste my 2 dozen arrows.

That is what I would do too, no point wasting that many shafts. Plus the extra 4# isn't going to speed things up much. You might shoot better at the lower draw weight too. :)

FireHawk Owner
10-11-2010, 07:28 AM
I backed mine down, To 60# to let a friend shot it to try it out.It seemed to be a lot louder to me.:( Hope it doesn't on yours..

RobD
10-11-2010, 08:20 AM
Well It worked I backed it down to 63#. Paper tuned it. S hotting bullet holes. Then I BH tuned it. My FP and BH are hitting exactly at the same spot at 30 YDS.:D .It doesn't seem much louder to me. Thank God..One more question, when I do change to a stronger spine, from 5575 to 7595 does the arrow weight change with a stronger spine?

Spiker
10-11-2010, 08:55 AM
Well It worked I backed it down to 63#. Paper tuned it. S hotting bullet holes. Then I BH tuned it. My FP and BH are hitting exactly at the same spot at 30 YDS.:D .It doesn't seem much louder to me. Thank God..One more question, when I do change to a stronger spine, from 5575 to 7595 does the arrow weight change with a stronger spine?

With a 29" arrow you will gain 20gn going from 5575 to 7595.
I shoot both sizes - identical otherwise - and they both have same poi out to 45-50 yds.
The 7595's group a bit better with fixed broadheads on them.

RobD
10-11-2010, 09:28 AM
With a 29" arrow you will gain 20gn going from 5575 to 7595.
I shoot both sizes - identical otherwise - and they both have same poi out to 45-50 yds.
The 7595's group a bit better with fixed broadheads on them.
Thats not much difference. but it should give me a little more penatration. That works.:cool:

RobD
10-11-2010, 09:31 AM
Found a great price on some 340 spines GT warriors. but never heard of them.any input.Some has to be up with them I pay that for a half dozen! http://shop.sportsmansguide.com/net/cb/1-dozen-gold-tip-warrior-carbon-arrows.aspx?a=705039

bfisher
10-11-2010, 10:30 AM
I never heard of the Warriors either. Most likely they are somethng in the quality range of Expeditions, but renamed for sale at one of the box stores. Sportman Guide often buys these up in volume and resells them. So long as the spine is right I wouldn't be afraid of them.

RobD
10-11-2010, 11:41 AM
Didn't think of that might be like the martin bows. Dicks sells them but renames them.