# Tuning problem



## sharkred7 (Jul 19, 2005)

OK all you tuning gurus out there I am in a serious quandary.

I have a Pro Comp that I cannot get to tune. I do most of my tuning with bare shaft. And for all you who believe in paper as the best way, my paper tune shows identical results.

I can NOT get my bare shaft to group with fletched arrows. The last time I went to the field range my groups exploded after 35 yards. I am a consistent 540+ shooter and my score dropped to 537 but my X count just tanked.

I am shooting a PCE at 53# with Vaps for field but now I'm trying to get some Fatboy 500's to tune. I am having the same results with BOTH arrows so I don't believe that is the culprit either. They are cut at 27.5 with 100 gr tips. 327 gr total. Archers advantage shows them very slightly weak at 53.5 but all my tuning results show them stiff.

My bare shafts are coming out of the bow sideways and hitting to left about 12" at 20 yards. This is the same bow I had shooting bare shafts in my fletched groups at 40 2 weeks ago. I'm a right handed shooter.

I have tried yoke tuning in both ways to the extreme, no change. I have tried moving the rest (a lot). I have cranked the poundage all the way up and down. I have switched the spacers around on the top cam. I have tried shooting them with zero face contact just looking through the peep and all same results.

My next move is to switch limbs around. Any one have any Ideas what could be going on? Bow is within specs.

Thanks
Confused


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## nuts&bolts (Mar 25, 2005)

sharkred7 said:


> OK all you tuning gurus out there I am in a serious quandary.
> 
> I have a Pro Comp that I cannot get to tune. I do most of my tuning with bare shaft. And for all you who believe in paper as the best way, my paper tune shows identical results.
> 
> ...


1) build a draw board
2) check top cam lean at full draw

pinch an arrow tight to the side of the top cam,
and see if the arrow runs parallel to the edge of the bowstring.

Smells like your arrow, will run UNDER the bowstring,
if you pinch the arrow to the LEFT side of your top cam.







THIS is zero cam lean, at full draw, on a draw board.


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## aread (Dec 25, 2009)

If the bow tuned, then didn't, something changed.

Is there damage to your rest? If you are using a spring steel launcher, you can get this type of results and barely be able to see the twist in the blade.
Is one of your limbs about to go? If it has broken fibers and is not rebounding with the same force, it could give this result.
Is you riser bent?
Have you changed your form, DL, anchors, etc?
Is your string about to go?
Is a cam bearing going bad?
Is a cam axel bent?


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## montigre (Oct 13, 2008)

sharkred7 said:


> I have a Pro Comp that I cannot get to tune. I do most of my tuning with bare shaft. And for all you who believe in paper as the best way, my paper tune shows identical results.
> 
> I am shooting a PCE at 53# with Vaps for field but now I'm trying to get some Fatboy 500's to tune. I am having the same results with BOTH arrows so I don't believe that is the culprit either. They are cut at 27.5 with 100 gr tips. 327 gr total. Archers advantage shows them very slightly weak at 53.5 but all my tuning results show them stiff.


This topic really should be asked under the forum, Bow Tuning. To get you started, you are overspined (dynamically) with the 500s at 53# and your DL. Drop down to 600s (maybe even 630s on the off chance) for your field endeavors and load the front up with 125gr and start to have fun again with your set up. Don't think of target arrows the same way you do your hunting arrows--the set up is greatly different....


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## sharkred7 (Jul 19, 2005)

montigre said:


> This topic really should be asked under the forum, Bow Tuning. To get you started, you are overspined (dynamically) with the 500s at 53# and your DL. Drop down to 600s (maybe even 630s on the off chance) for your field endeavors and load the front up with 125gr and start to have fun again with your set up. Don't think of target arrows the same way you do your hunting arrows--the set up is greatly different....


According to AA I'm underspined and the these arrows tuned before. I have switched limbs. and axles. The only thing left ot change is the cam and I will do that also. I will also change the spring steel, if it could only be that easy. I posted it here because I am an advanced archer with a problem I've never seen before and I want peoples input who also have some string time behind them,not every Joe who thinks he is an expert. I have been all over the tuning forum also.
Very frustrating.


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## sharkred7 (Jul 19, 2005)

nuts&bolts said:


> 1) build a draw board
> 2) check top cam lean at full draw
> 
> pinch an arrow tight to the side of the top cam,
> ...


Thanks. I will double check that again. I do have a draw board and it looks to me like I have excessive cam lean on the bottom. I will take pics tomorrow and try to post them


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## montigre (Oct 13, 2008)

sharkred7 said:


> According to AA I'm underspined and the these arrows tuned before. I have switched limbs. and axles. The only thing left ot change is the cam and I will do that also. I will also change the spring steel, if it could only be that easy. I posted it here because I am an advanced archer with a problem I've never seen before and I want peoples input who also have some string time behind them,not every Joe who thinks he is an expert. I have been all over the tuning forum also.Very frustrating.


Then I agree with Allen, if the bow tuned well before and suddenly it is not, then something has changed. Since you already changed out the limbs, the next usual culprit is the blade if you're working with a good string set. A small bend or crack in the blade will give someone very wild results. Also, once this is cleared up, do not discount the dynamic spine issue for future evaluation. You really are on the border of being overspined (again dynamically) with the 500s and a 100gr point... AA only gives a person a rough starting point and is based on a set of archers' shot averages and not empirical data.


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## bigHUN (Feb 5, 2006)

BS hitting left from fletched arrows (hitting your side relative to riser) means stiff arrows.... 
to quickly prove this turn down the limbs 2 turns (I believe you will need more then 2x) and you will see the 12" distance will shrink. 
First available time you need to check your cam alignment in full draw and static position, may happen easily you will have to average it out. 
The launcher blade crack will also throw the arrows all over the place.
Timing on cams? Where is your nocking point relative to the resting point height? Me personally like to keep less then 1 millimeter offset and not more, so minimum clearance...(you switching carbon OD right?)
I just have this exercise with my transfer from DST40 (with large cams) to DST38 (with medium cams) the new limbs/cams are way more powerful and my surprise is that it wasn't enough me to cut the carbon length (CX nano XR410's) from 28.95" to 27" (120 gr points) but also I have to lower the limb power from #57.8 to #53.... the arrows were flying kind of OK (wide open loose in a yellow @ 50 meters) but won't group tight in a 10 ring....so I am getting the large cams for the bow (will slow down the KE/speed) so I can get back up the limbs to #57 comfort level....


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## bigHUN (Feb 5, 2006)

bigHUN said:


> BS hitting left from fletched arrows (hitting your side relative to riser) means stiff arrows....
> .....to quickly prove this turn down the limbs 2 turns....


sorry my bad in the above direction, but you got the picture, turning up/down the limb power (on a cable guarded bow at least) will definitely show in one or the other way the stiff or weak spine.
Also I would bet in order you to get a POI your pin or dot is well out to left, right? The french tune can work only within a reasonable range if the spine calculation is greatly off you know what you have to do...


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## SonnyThomas (Sep 10, 2006)

It was shooting and now it isn't and there were no changes? Are you sure? Different d-loop material even, release, thickness of blade? If so, you look to you...

I've had a few Hoyts, 12 I think, most were UltraTecs and the last a ProElite. All but 2 had cam & 1/2s. So all 10 at one time another had floating yokes and static yokes. I had no issues with either type yoke. All the cam & 1/2 systems were timed through Javi's draw stop tuning and all ended up with a string nock setting of 1/16" or danged close and none went higher than 1/8". 

No way on God's green earth do I believe in swapping limbs end for end. Going 15 years and not once have I heard or seen of this correcting anything. And if it did it was because whoever corrected something that was wrong to begin with and whoever didn't catch or see. I swapped limbs once to prove that the customers bow had to different poundage limbs.... Ripped paper 6 inches low and swapped limbs gave 6 inches high. 

Cam lean. With static yokes I adjusted until the cam was straight with the bow string. Most all my target bows had offset guide rods and these were adjusted to give clearance of the vane being used. Long ata bows do not aggravate, add to cam lean as do short ata bows. So a small difference in cam at full draw from bow at rest. In most cases correcting cam lean at full draw, so it's straight, is more of a trade off. In other words, you have cam straight with bow at rest and X amount cam lean with bow at full draw. With cam straight at full draw you have the same X amount of cam with bow at rest. So both giving same lateral string movement, but from different points. Bows being mechanical they repeat time after time after time. That they repeat we can compensate.

Bare shaft tuning... You have to be more perfect with a bare shaft. Bare shaft tuning is not the final word. Your fletched arrow being both accurate and grouping is the final word.

One of two things. Either I can't bare shaft tune or my bows won't bare shaft tune. My last 5 bows haven't had yokes. Two didn't have offset guide rods. All were/are pin point accurate. One of my UltraTecs is a absolute nightmare for cam lean, a 2000 UltraTec with single Red Line cam. Cam leans one way and top wheel leans the opposite (floating yoke). It hangs on my wall because it did it all, 3D, Indoor, Outdoor and Field....

Note; PMed with ontarget7 while trying to bare shaft tune. Shane probably does bare shaft tuning better than anyone I know. Have you contacted him?

Bare shaft results aren't working, have you tried another tuning method? I use two manners of French tuning, a short distance version of 9 to 10 feet and 30/35 yards and the other 9 to 10 feet out to as far as I can stay on the target bale, usually 55 and 60 yards. Dead on at 55 and 60 yards I may play with nock or rest position to see if groups can be tightened. 

Pictures from my present bow, Pearson MarXman, no yokes. Best it will do bare shaft tuning (20 yards). The sort of jigsaw picture, has top right 5 hits on the line 10 feet (I ain't that picky), bottom right showing the busted nock and then . 55 yards while French tuning and not done. If you believe in the deemed best FOC, then consider that my arrows checked in the two different manners, 6.02% FOC and 6.23%. Maybe 10% would be better, but I don't compete much farther than 45 yards at local 3D clubs and 40 yards is the max for ASA Super Seniors.


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## TNMAN (Oct 6, 2009)

Big right tear that can't be corrected with yokes or rest--- You may need to shim bottom cam to move it over a little to the right. Recommend see tmorelli thread in over in the pse brand specific forum for a good explanation.


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## sharkred7 (Jul 19, 2005)

Thanks for all the suggestions. 

I didn't swap limbs top to bottom. Would never do that either. Just swapped left and right. No change so that rules out a cracked limb which was my fear. I have my rest out to just shy of one inch from riser. Seams to be much better. Due to the bigger shoot through window? My pin is in line with the arrow, top cam lean even at full draw on draw board with all stabs in place. The next step will be French and group tuning. May be that's what it takes with this bow.


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## dua lam pa (May 29, 2014)

sharked7 - why do you insist on bareshafts hitting with dressed arrows ?
placing undue torque in the bow to force bare shafts to contact with fletched arrows will create stress on your cables and string 
this stress creates a never ending change in torque on your strings , which equates to your cables and string never setting in to your shot . 

Why not just set the bow up straight and clean ? Simply shoot a consistant shot out of a stable set up ?
If bare shafts happen to hit together great -
what if they hit at 10 yards and not 20 yards ?
what if bare shafts does not hit POA at 50 yards ? ( it wont ) 
what if the wind addresses the fletch and the bare shaft ?


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## JAVI (Jun 19, 2003)

If the bow was tuned with the same arrow before and nothing has changed (i.e. draw weight, draw length) then I suspect a dragging cam bearing. Wonder it you changed servings or nocks since the bow tuned...


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## montigre (Oct 13, 2008)

Welcome back, Javi--you've been missed around these parts! :cheers:


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## SonnyThomas (Sep 10, 2006)

Javi, long time, sir. Got out of the lawn chair to stretch your legs, huh? 

Class, pay attention....


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## aread (Dec 25, 2009)

JAVI said:


> If the bow was tuned with the same arrow before and nothing has changed (i.e. draw weight, draw length) then I suspect a dragging cam bearing. Wonder it you changed servings or nocks since the bow tuned...


Mike, great to see you posting here again! Don't be a stranger. Like Gail said, you've been missed.

Allen


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## hooks (Mar 22, 2005)

JAVI said:


> If the bow was tuned with the same arrow before and nothing has changed (i.e. draw weight, draw length) then I suspect a dragging cam bearing. Wonder it you changed servings or nocks since the bow tuned...


Awesome to hear from you again JAVI! Thanks for posting.


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## N7709K (Dec 17, 2008)

Pce's tune stiff- so you need to build accordingly. Go stiffer in spine or shim the cams closer inside and tune inside. 

Are vaps and fatboys the only options you have?

It could be a cam bearing; but they usually don't open groups up much, maybe 1/4"-1/2" at the distance you're talking. Is there a buzz in the cams or do you feel a drag as you roll them?


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## just ulgy (Aug 23, 2012)

Hey John I think its time you give me a call. I think your spending way to much time tearing things apart than concentrating on your shooting. lets use the kiss method and get you back to shooting the way I know you can.

Mike


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## rossing6 (Jun 7, 2008)

One of the first things you should do with those tuning symptoms is put a bent cable guard rod on there to get rid of a lot of the torque at full draw. I work on a lot of bows with similar issues, and when cam shimming and poundage changes and all the above don't work, it indicates riser torque, get a bent bar or tilt tamer style and it'll make a world of difference. I buy the polished aluminum 3/8" rod at Lowes locally, and cut and bend them custom per bow, yours is probably 8-9" max the way they are mounted, you can easily make one. 

Then tune up as always. It's a very simple fix. Ryan


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## rafca_age (May 21, 2014)

hold up check the limbs for parallel cracks going from the limb bolt to the cam the some times look like hairlines so they are easy to miss may not even be visible unless at full draw also putting in a bent cable bar sounds good too


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## sharkred7 (Jul 19, 2005)

Thanks for all the input guys. I got her shooting pretty well out to 50. 
Will let you know how it goes when I get to longer distances after next week


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## Joe Schnur (Mar 22, 2012)

Well you never came back


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## fanio (Feb 1, 2011)

Yeah, how did things go and did you get the problem fixed? Many of us seem to have this problem with the PCEs.


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## sharkred7 (Jul 19, 2005)

Ahhhh well I was hoping this thread would never resurface:embara:. I found the culprit.....my bare shaft had a wobble in it. I found it when I flipped my arrow to the opposite side up. When the cock feather side was up it hit the same spot, when down it was low left. That is what finally got me thinking about the arrow itself. It was not straight, didn't even think about that with a carbon arrow. Some times the answer is TOO obvious.:embara:


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## sharkred7 (Jul 19, 2005)

fanio said:


> Yeah, how did things go and did you get the problem fixed? Many of us seem to have this problem with the PCEs.


I know, they do seem a little finicky. Group tuning seems to be the way to go. Bareshafting my PCE was frustrating. I did find a problem with excessive face contact by doing this though.


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## Joe Schnur (Mar 22, 2012)

Thanks for chiming back in nice to see closure


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## Huntinsker (Feb 9, 2012)

sharkred7 said:


> Ahhhh well I was hoping this thread would never resurface:embara:. I found the culprit.....my bare shaft had a wobble in it. I found it when I flipped my arrow to the opposite side up. When the cock feather side was up it hit the same spot, when down it was low left. That is what finally got me thinking about the arrow itself. It was not straight, didn't even think about that with a carbon arrow. Some times the answer is TOO obvious.:embara:


Yep, it's always a good idea to use multiple bareshafts in case you have a dud. I fletch 9 and keep 3 bare for tuning and practice.


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