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Cnight
08-07-2012, 07:08 PM
I have been trying to paper tune my bow and cannot tune out the left tear. I am shooting goldtip xt hunter 7595 arrows cut to 28" with 100grain tips. my bow is turned up to around 70#. Not sure on the exact dw but should be close. I do not know were I need to go from here with tuning. Do I just need to turn my bow down or is there somthing I am missing?:confused:

bob cooly
08-07-2012, 07:35 PM
Shoot a bare shaft, if it goes through clean I would look for fletching contact on your rest.

Cnight
08-07-2012, 10:25 PM
Forgot to mention I am using a wisker biscuit rest so fletching contact is out of the question.

archerx7
08-08-2012, 10:45 AM
With your 27" DL, the 7595's are going to be too stiff with 100gr points even at 70#'s. The 5575's would spine out perfect cut to 28" with 100gr points at 70#'s. You may be able to get the 7595's to work, but you'll need to go up to at least 125gr points and probably have to play around with the idler lean and center shot to get the left tear out. If you have wraps under the vanes, remove them as they will also increase an arrows spine and refletch using a small light weight vane such as a 2" blazer, fuzion or predator. Adding weight to the nock end increases spine while adding weight to the front decreases spine.

Cnight
08-08-2012, 12:17 PM
Well I need to check for sure but my actual dl is 28 to 28 1/2". According to the gt arrow chart this is the arrow I need. I have some 5575s but cant get them to tune either. One interesting note the xt hunters are a 340 spine but I also have some xt velocities wich are a 300 spine. My velocities with a screw in 100 grain tip dont tune either but I have 2 that have 100 grain glue in points that shoot perfectly through paper. Why is this because there is less weight at the front of the shaft cause there is no insert:confused: I really dont want to get new arrows but if I have to I have to i guess. Unless you guys think a 125 grain point will work.

polaris754
08-08-2012, 10:34 PM
Holey batman! archer 7 that was a mouth full , dose seem that u narrowed it down. ONE OF THOSE DO DADS SHOULD FIX IT ! cant think that ur wrong should do him right!GOOD LUC!

Phantonza
08-09-2012, 04:56 AM
With your 27" DL, the 7595's are going to be too stiff with 100gr points even at 70#'s. The 5575's would spine out perfect cut to 28" with 100gr points at 70#'s. You may be able to get the 7595's to work, but you'll need to go up to at least 125gr points and probably have to play around with the idler lean and center shot to get the left tear out.


I disagree. Too stiff arrow should not be a problem. In contrast, too weak arrow can cause tear sideways.

A couple of questions:
- do you have the arrow rest set at the correct height (arrow is at the height of the arrow rest's mounting hole)?
- have you checked cam lean?

With my previous bow (Hoyt CRX 32) I could not get rid of a slight left tear even though I adjusted the cam lean to zero. However, I achieved good results with broadhead tuning: same point of impact with field points. At that point, I decided not to worry about the slight tear in paper. It was kind of strange because I think you should get equal results with both tuning methods - that is, same point of impact with field tips/broadheads would mean a bullet hole in paper.

How long is the left tear?

Cnight
08-09-2012, 06:15 AM
My tear is about 1.25 inches from 10 feet. I have set cam lean as close to zero as possible.

elkslayer4x5
08-09-2012, 07:49 AM
You can increase tuneabilty by refletching with Gateway Rayzrs which are 500% lighter than plastic vanes, according to their information in the Lancaster catalog. They claim to increase the usable spine range of your Arrrows. Feathers also provide more stabilty than vanes do, the down side to feathers is they have more air drag, and will decrease your arrow speed out past 50 yds.

Phantonza
08-09-2012, 07:56 AM
My tear is about 1.25 inches from 10 feet. I have set cam lean as close to zero as possible.

OK... And naturally you have tried to adjust the arrow rest sideways.

- are you sure you have not over-adjusted the rest to the right so that there would be fletching contact to the riser?
- what about your grip hand - do you think you have a correct grip with no squeezing (that could induce torque)? I have seen incorrect grip cause tear in paper test.

archerx7
08-09-2012, 10:19 AM
Well I need to check for sure but my actual dl is 28 to 28 1/2". According to the gt arrow chart this is the arrow I need. I have some 5575s but cant get them to tune either. One interesting note the xt hunters are a 340 spine but I also have some xt velocities wich are a 300 spine. My velocities with a screw in 100 grain tip dont tune either but I have 2 that have 100 grain glue in points that shoot perfectly through paper. Why is this because there is less weight at the front of the shaft cause there is no insert:confused: I really dont want to get new arrows but if I have to I have to i guess. Unless you guys think a 125 grain point will work.

Thought I saw 27" DL in your sig line when I responded, my bad. Which mod do you have installed on the cam? If you are a 28-28.5 DL that will make a big difference in how close these arrows are to being the correct spine.You may have the centershot off a bit and you will probably need to put a bit of lean into the idler to get the tear out.Start with zero lean in the idler and Reset the centershot on the rest so the arrow is inline with the string as it comes off the cam/idler tracks and make your centershot adjustments in very small increments......no more than 1/16" at a time as its very easy to go right past the optimum setting. Once you get the tear down to as small as possible, start adding some lean to the idler
one twist at a time on the left side yoke to lean the idler toward the ccs(assuming this is a RH bow). If the tear gets worse......start leaning the idler in the other direction one twist at a time in the right side of the yoke.

I've setup and tuned more than a few Panteras, as long as the arrow spines out fairly close it shouldn't be very difficult to get tuned, let us know which mod is on the cam and I can tell you how close the spine is to being correct.



I disagree. Too stiff arrow should not be a problem. In contrast, too weak arrow can cause tear sideways.

Too stiff an arrow can and will be a problem and result in a horizontal tear just the same as an arrow thats too weak, only the tear will generally be in the opposite direction........depending on where the centershot is set at, what type of rest is being used and what type of cable containtment system is on the bow. Generally, a stiff arrow is a little easier to broadhead tune than a weak arrow, but again that all depends on the bow in question, if it has a rollerguard system for containing the cables, a borderline weak shaft will usually tune a little easier than a borderline stiff shaft.

Phantonza
08-09-2012, 02:43 PM
Too stiff an arrow can and will be a problem and result in a horizontal tear just the same as an arrow thats too weak, only the tear will generally be in the opposite direction........


I agree, but only if we are talking about finger shooting. I assumed we were talking about using a release aid, and in that case I think an over stiff arrow can be easily tuned to produce bullet holes in paper tuning.



Generally, a stiff arrow is a little easier to broadhead tune than a weak arrow, but again that all depends on the bow in question, if it has a rollerguard system for containing the cables, a borderline weak shaft will usually tune a little easier than a borderline stiff shaft.

The rule of thumb that I have learned that it is always better to have the arrow slightly in the stiff side than on the weak side, if you are about to shoot accurately with broadheads.

Cnight
08-17-2012, 05:58 PM
Sorry I have'nt posted any results yet. I went out a few days ago an paper tuned so I was getting the least left tear I could get. I also tried heavier and lighter points but nothing helped. So I decided to adjust tiller because it was out anyway. I shot through paper and it bullet holed perfectly so I dont know what that would have done to make it shoot better.

B4L Okie
08-17-2012, 11:18 PM
I would lose the biscuit and get a good drop away rest. Oh the '11 pantera should have a bar cable guard/slide whereas the '10 will have the ccs