# Broad head vs. field point POI Problems



## srcarlso (Mar 3, 2005)

*Tuning*

Sounds like you need to tune the bow for field points. Generally, for that much difference, you are likely getting planing of the broadhead....the arrow is not coming off the bow right and your broadhead is acting like a front rudder. You can chase it but this much of a difference is best remedied by trying bow tuning first.


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## dormin (Oct 9, 2006)

Once you get it tuned here's a link that was helpful to me

http://www.archerytalk.com/vb/showthread.php?t=539460

Good luck!


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## gbear (May 30, 2009)

use the link above 
there is a lot of good info deep inside from all who posted. read the whole thing. 
things to check besides rest--move d-loop instead, arrow spine, 

also do a search for modified walkback tuning by nuts&bolts

I only have to do the most minor adjustments for broadhead tuning when i use this method. It's quick to do, i can tune a bow in just a couple hours and have the bh's flying with the fp's.


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## psu111376 (Aug 4, 2009)

Thanks for the link and the suggestions. What order should I procede to tune; paper, bare shaft, walk back? I have been reading about these different but haven't figured out which to do first or if only one is needed?


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## BIG-GAMER (Aug 8, 2009)

did i understand u right that u can make bh fly like field tips


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## Jathinkysaurus (Oct 8, 2006)

psu111376 said:


> Thanks for the link and the suggestions. What order should I procede to tune; paper, bare shaft, walk back? I have been reading about these different but haven't figured out which to do first or if only one is needed?


Here's what I do:
1; check that everything is in spec- AtoA, brace height, cam lean etc
2; set rest height with arrow centred across berger hole, set nock height as recommended for your bow e.g. 1/4" high
3; set rest to centre with arrow parallel to riser (I use a straight-edge, you can buy a laser if you like spending money)
4; walkback tune with fletched field points to align centre shot.
5; bare shaft tune to set nock height. At this stage, if there is a left/right difference between bare and fletched shafts, I tweak the limb bolts as it is a spine issue.
6; once bare shaft and flethed shafts with FPs are hitting together from at least 15 yards (preferably 25-30), I fine-tune with broadheads. 

The fine-tuning at steps 5 and 6 are done with the limb bolts, i.e. for stiff spine symptoms increase draw weight by tightening the limb bolts a little, for weak spine symptoms decrease draw weight by backing them both off a little, to slightly raise the nock point tighten the top limb bolt and back the bottom limb bolt off the same amount, to slightly raise the nocking point and increase draw weight tighten the top limb bolt a little, etc. A quarter turn at a time at most with the limb bolts.

When bare-shaft tuning I always wrap tape around the back end of the arrow so that weight and balance are identical to my fletched arrow, otherwise dynamic spine will differ between the two and the exercise will be pointless.


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## psu111376 (Aug 4, 2009)

Jathinkysaurus said:


> Here's what I do:
> 1; check that everything is in spec- AtoA, brace height, cam lean etc
> 2; set rest height with arrow centred across berger hole, set nock height as recommended for your bow e.g. 1/4" high
> 3; set rest to centre with arrow parallel to riser (I use a straight-edge, you can buy a laser if you like spending money)
> ...


I tried to apply all the suggestions that applied to my setup. First I checked the specs and all seemed to be in order. I double checked the rest position: the top of the arrow sits near the bottom of the Berger hole and the nock point is/was 1/8 above square. 

I didn't adjust anything at that this point but continued to walk back tune, to determine the center shot. It was right on out to 40 yards; shooting field points, groups of 4 (ruined two fl etchings due to tight groups)

I don't have any bar shafts, so I didn't bare shaft tune. I did shoot through paper to see what kind of arrow flight I had (look good by eye). No tears in the paper. 

Proceeded to broad head tune as the link in one of the previous post showed. Move rest up to "chase" the field points with the broad heads. This did not narrow the vertical separation any and caused terrible arrow flight (terrible kick out to the left). After many vertical adjustments with no improvement, I moved the rest to the left to try to get better arrow flight (hoping to help POI). No help, just moved the POI for both to the right. 

Continued this for over 2 hours with no improvement. So, now I have a bow that is terribly out of tune and no idea what to do. I am so frustrated that I am dreading having to shot again.

I do have a couple of questions:

1) what is the theory behind the 1/4 high of square for the nock point?
2) what is the significant of centering the arrow in the berger hole.
3) what are the symptoms of a broad head flight and POI on an over spined arrow?


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## Duck65 (Nov 30, 2005)

1/4 inch high of square with nock point does not sound right. But I sure aint no expert.


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## bfisher (Nov 30, 2002)

psu111376 said:


> I tried to apply all the suggestions that applied to my setup. First I checked the specs and all seemed to be in order. I double checked the rest position: the top of the arrow sits near the bottom of the Berger hole and the nock point is/was 1/8 above square.
> 
> I didn't adjust anything at that this point but continued to walk back tune, to determine the center shot. It was right on out to 40 yards; shooting field points, groups of 4 (ruined two fl etchings due to tight groups)
> 
> ...


 #1. The 1/4" above square is kind of a misnomer. Assuming you use a bowsquare, snap it on the string and lower it down to the rest. The 1/4" measurement is usually about where the top of the nock would be, so in essense the arrow really ends up about square to 1/8" above square depending on arrow diameter and nock type used.

#2. I've never understood this centering on the Berger hole either. Bows used to have the grip in the vertical center of the bow so the berger hole was higher than it is today, by about 1 1/2" and we were able to tune those bows just as well as today. Within reason, I don't think it makes that much difference where the arrow is. You still tune the bow for any differences. I guess some people think the Berger hole is vertically centered between the axles but this isn't so. Sometimes a slight tiller adjustment can compensate for this.

#3. I can't answer with any certainty.


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## srcarlso (Mar 3, 2005)

*dump the square*



Duck65 said:


> 1/4 inch high of square with nock point does not sound right. But I sure aint no expert.


Get rid of the bow square and get a set of levels for setting up bows. One snaps to the string, one on the arrow. Level the string then set up the arrow level (or better yet just pointing down enough the bubble touches the line nearest the bow). 

If you have a single cam bow...the square is not going to work well anyway. Is this case you need to level the arrow shelf then the arrow...especially for Mathews bows.


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## lenny288 (Sep 16, 2005)

What rest are you using? Sounds like a similar problem I had.


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## TMan51 (Jan 25, 2004)

psu111376 said:


> I don't have any bar shafts, so I didn't bare shaft tune. I did shoot through paper to see what kind of arrow flight I had (look good by eye). No tears in the paper.


I find that bare shaft tuning, starting at 6', is the easiest way to get to the point where BH tuning is productive. If the bow isn't that close to being tuned, the addition of a fixed blade head can give a lot of confusing signals to the tuner. I like to have the bow shooting pretty much straight to at least 20', and 30' is better.

Chasing the FP, is the way BH tuning works. When you have a combination that gets to a point where they don't come together, and they "chase" each other, it's almost always because You're under/over spined for the combination and you need to add/remove tip weight, or add/reduce draw weight.

BH tuning is a matter of keeping the arrow on a line to the Point of Aim, until the arrow starts to spin, and before the BH starts to steer the arrow. Once the shaft is spinning, the arrow will travel in the direction it was going when it was stabilized by the fletching spinning the shaft. Depending on the fletch, and the amount of offset, that will be about 10-20ft.


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## reubin williams (Feb 22, 2009)

If you can't get them to impact together, forget the field points and adjust sights for broadheads or change to expandables. Reubin


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## IlBuckMaster (Nov 14, 2005)

One thing that I can think of that nobody has mentioned would be to ensure that you are not putting too much pressure on the string with your nose / face when you are at full draw and preparing to shoot.

This will cause a broadhead to plane high relative to a field point. But it should also cause a slightly low tear thru paper.

The other suggestion is to retune your bow so that the top of the arrow is at the top of the berger hole - and shooting a bullet hole. Bows / cams are designed to have an arrow nocked at a certain place on the string to ensure level nock travel at the point of release - especially older single cams. If you move the nocking point higher or lower than this - you can have trouble with broadhead flight and tuning. It sounds like you have the rest and nocking point a little lower than what you should have for that particular bow.

Hope one of these two helps you.

Scott


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## deadlysilent (Sep 6, 2009)

*Great thread*

I am having the exact same problem. Been looking for answers. Tried a walk back tuning and could not resolve issue. I am reflecting on changes that have been made to my bow since last season. New rest (new whisker biscuit replacing old), new shafts (ICS 340) and new #.... took it up to 70# thinking I was being smart. I think that must be what is causing my issue. I will be backing it down to 65# tomorrow and rechecking everything. I will post results until such time as I can claim success.
Does anyone know if there is a specific test for spining issues?


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## Jathinkysaurus (Oct 8, 2006)

I may have been inadvertently misleading in my response above where I said 'set the nock point as recommended for your bow, e.g. 14" high'; I was not saying that 1/4" high is what is recommended for your bow- I don't know what is recommended for your bow. Do a bit of searching or ask others with the same equipment, what is the recommended nock height or what nock height others have found works well on that model. What I meant was, for some models they work well at 1/4" high, others work well dead level, others 1/8' high etc. Sorry if that caused you confusion.
You said that you damaged fletchings when walkback tuning- if you're prepared to strip the fletching off one of the arrows that are going to need re-fletching anyway, you can then bare-shaft tune with it before getting it re-fletched. I personally have found bare-shaft tuning to be the best and quickest method for getting things where they should be.
Download the Easton tuning guide and have a good read, it will give you a very good understanding of the effects of over-spined and under-spined arrows so that you can make sense of the results you are getting. 
You really need to have a sequential plan for how you are going to get the bow tuned, and go through it step by step. Skipping one or more steps and fiddling back and forth will just cause frustration.
Another thing I should have added in there with 'make sure everything is in spec'; make sure your broadheads spin true on the arrows. They absolutely MUST be dead straight on the shafts.
Good luck. It can be a frustrating process, but if you approach it methodically and get one thing set right before you move on to the next thing, you will get good results. It's very satisfying when you've finally got it sorted and your broadheads shave the vanes off your field-tipped arrows at 60 yards.


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## Jathinkysaurus (Oct 8, 2006)

reubin williams said:


> If you can't get them to impact together, forget the field points and adjust sights for broadheads or change to expandables. Reubin


I used to do this. In fact, a dealer told me that it was impossible to get broadheads and field points to hit in the same place, and sold me a second sight so that I could swap sights (dovetail mounted) between practicing and hunting.
Problem with this is that broadhead tuning problems indicate poor arrow flight. The arrows will be planing in flight and losing energy, they will probably also impact very slightly side-on, resulting in loss of penetrating power. At longer ranges you may get very little penetration.
Also if you can tune it properly instead of compensating for poor tuning, your broadhead groups will be tighter- meaning more accurate.


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## Duck65 (Nov 30, 2005)

Jathinkysaurus said:


> I used to do this. In fact, a dealer told me that it was impossible to get broadheads and field points to hit in the same place, and sold me a second sight so that I could swap sights (dovetail mounted) between practicing and hunting.
> Problem with this is that broadhead tuning problems indicate poor arrow flight. The arrows will be planing in flight and losing energy, they will probably also impact very slightly side-on, resulting in loss of penetrating power. At longer ranges you may get very little penetration.
> Also if you can tune it properly instead of compensating for poor tuning, your broadhead groups will be tighter- meaning more accurate.


Very well put.:rock:


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## 3children (Aug 10, 2008)

In other words, a straight shot out of the bow arrow, will fly faster and penatrate more if the arrow is not flying some type of sideways. Did I say that right? Tuning the bow with fp and shooting thru paper is the start! Why not do the same with your bh's. Why not shoot thru paper? Yes it is one more thing to do but you owe it to the game you shoot. Good shooting!!!!


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## deadlysilent (Sep 6, 2009)

Tested for spining issue using the bare shaft test. I am screwed. POI of bare shaft was consistently left of fletched shaft. I already have the bow at max draw weight of 70#. I pulled an original carbon shaft carbon hunter from Cabela's and had nearly the same result. It was a little less severe but none the less... left of fletched shafts. The only thing I did not think to try was a 125g tip. Just thought of it as I write this post! Has to be something else though. SO FRUSTRATING!!!!!! Please tell me if you have experienced similar problems.


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## TMan51 (Jan 25, 2004)

deadlysilent said:


> The only thing I did not think to try was a 125g tip. .


Or, depending on the type of insert, you may be able to install PDP insert weights. They have the same thread as the tip, and can be installed from the nock end.

I have a pile of CAA 400's that tune stiff from my 60lb bows with a 125gr tip. Installing the 20gr GT insert weights fixes that immediately, and provides a better FOC in the mix. It barely affects speed/drop form the bows I've tried them on.


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## Roskoe (Apr 15, 2007)

This entire thread is pretty much the classic story of what often happens when you start out the tuning process without knowing that your arrows are spined right. You just chase your tail around for weeks and can't get things to work out. Gotta get that arrow spine issue right before moving to the other steps in the process.


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## psu111376 (Aug 4, 2009)

deadlysilent said:


> Tested for spining issue using the bare shaft test. I am screwed. POI of bare shaft was consistently left of fletched shaft. I already have the bow at max draw weight of 70#. I pulled an original carbon shaft carbon hunter from Cabela's and had nearly the same result. It was a little less severe but none the less... left of fletched shafts. The only thing I did not think to try was a 125g tip. Just thought of it as I write this post! Has to be something else though. SO FRUSTRATING!!!!!! Please tell me if you have experienced similar problems.


I am thinking that my arrow are over spined as well.


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## deadlysilent (Sep 6, 2009)

For the record, I attempted the bare shaft test with 125g FP and it did make a difference. Unfortunately, even with the full length Cabela's Carbon Hunter shaft, it was vastly improved, but it is still testing to be over spined. I am looking for a local pro shop to get another opinion on the setup. will continue to post updates.


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